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1552 lines
91 KiB
1552 lines
91 KiB
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html lang="en-US-x-Hixie" ><head><title>4.3 Scripting — HTML5 </title><style type="text/css">
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pre { margin-left: 2em; white-space: pre-wrap; }
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h2 { margin: 3em 0 1em 0; }
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h3 { margin: 2.5em 0 1em 0; }
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h4 { margin: 2.5em 0 0.75em 0; }
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h5, h6 { margin: 2.5em 0 1em; }
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h1 + h2, h1 + h2 + h2 { margin: 0.75em 0 0.75em; }
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h2 + h3, h3 + h4, h4 + h5, h5 + h6 { margin-top: 0.5em; }
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p { margin: 1em 0; }
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hr:not(.top) { display: block; background: none; border: none; padding: 0; margin: 2em 0; height: auto; }
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dl, dd { margin-top: 0; margin-bottom: 0; }
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dt { margin-top: 0.75em; margin-bottom: 0.25em; clear: left; }
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dt + dt { margin-top: 0; }
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dd dt { margin-top: 0.25em; margin-bottom: 0; }
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dd p { margin-top: 0; }
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dd dl + p { margin-top: 1em; }
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dd table + p { margin-top: 1em; }
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p + * > li, dd li { margin: 1em 0; }
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dt, dfn { font-weight: bold; font-style: normal; }
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dt dfn { font-style: italic; }
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pre, code { font-size: inherit; font-family: monospace; font-variant: normal; }
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pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
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pre em { font-weight: bolder; font-style: normal; }
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@media screen { code { color: orangered; } code :link, code :visited { color: inherit; } }
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var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
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table { border-collapse: collapse; border-style: hidden hidden none hidden; }
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table thead, table tbody { border-bottom: solid; }
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table tbody th:first-child { border-left: solid; }
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table tbody th { text-align: left; }
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table td, table th { border-left: solid; border-right: solid; border-bottom: solid thin; vertical-align: top; padding: 0.2em; }
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blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }
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.bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
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.matrix, .matrix td { border: none; text-align: right; }
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.matrix { margin-left: 2em; }
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.dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
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.dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
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.dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
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.toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
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img.extra { float: right; }
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pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; }
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pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
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pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
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pre.css:first-line { color: #AAAA50; }
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dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #DDFFDD; }
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hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
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dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
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dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
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dl.domintro dd p { margin: 0.5em 0; }
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dl.switch { padding-left: 2em; }
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dl.switch > dt { text-indent: -1.5em; }
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dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
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dl.triple { padding: 0 0 0 1em; }
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dl.triple dt, dl.triple dd { margin: 0; display: inline }
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dl.triple dt:after { content: ':'; }
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dl.triple dd:after { content: '\A'; white-space: pre; }
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.diff-old { text-decoration: line-through; color: silver; background: transparent; }
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.diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
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a .diff-new { border-bottom: 1px blue solid; }
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h2 { page-break-before: always; }
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h1, h2, h3, h4, h5, h6 { page-break-after: avoid; }
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h1 + h2, hr + h2.no-toc { page-break-before: auto; }
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p > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]),
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li > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]), { border-bottom: solid #9999CC; }
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div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
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div.head p { margin: 0; }
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div.head h1 { margin: 0; }
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div.head .logo { float: right; margin: 0 1em; }
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div.head .logo img { border: none } /* remove border from top image */
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div.head dl { margin: 1em 0; }
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div.head p.copyright, div.head p.alt { font-size: x-small; font-style: oblique; margin: 0; }
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body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
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body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
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body > .toc > li > * { margin-bottom: 0.5em; }
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body > .toc > li > * > li > * { margin-bottom: 0.25em; }
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.toc, .toc li { list-style: none; }
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.brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
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.brief li { margin: 0; padding: 0; }
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.brief li p { margin: 0; padding: 0; }
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.category-list { margin-top: -0.75em; margin-bottom: 1em; line-height: 1.5; }
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.category-list::before { content: '\21D2\A0'; font-size: 1.2em; font-weight: 900; }
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.category-list li { display: inline; }
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.category-list li:not(:last-child)::after { content: ', '; }
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.category-list li > span, .category-list li > a { text-transform: lowercase; }
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.category-list li * { text-transform: none; } /* don't affect <code> nested in <a> */
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.XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
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.XXX > :first-child { margin-top: 0; }
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p .XXX { line-height: 3em; }
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.annotation { border: solid thin black; background: #0C479D; color: white; position: relative; margin: 8px 0 20px 0; }
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.annotation:before { position: absolute; left: 0; top: 0; width: 100%; height: 100%; margin: 6px -6px -6px 6px; background: #333333; z-index: -1; content: ''; }
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.annotation :link, .annotation :visited { color: inherit; }
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.annotation :link:hover, .annotation :visited:hover { background: transparent; }
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.annotation span { border: none ! important; }
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.note { color: green; background: transparent; font-family: sans-serif; }
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.warning { color: red; background: transparent; }
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.note, .warning { font-weight: bolder; font-style: italic; }
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p.note, div.note { padding: 0.5em 2em; }
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span.note { padding: 0 2em; }
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.note p:first-child, .warning p:first-child { margin-top: 0; }
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.note p:last-child, .warning p:last-child { margin-bottom: 0; }
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.warning:before { font-style: normal; }
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p.note:before { content: 'Note: '; }
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p.warning:before { content: '\26A0 Warning! '; }
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.bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
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.bookkeeping { font-size: 0.8em; margin: 2em 0; }
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.bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }
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.bookkeeping dt { margin: 0.5em 2em 0; }
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.bookkeeping dd { margin: 0 3em 0.5em; }
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h4 { position: relative; z-index: 3; }
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h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
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.element {
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background: #EEEEFF;
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color: black;
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margin: 0 0 1em 0.15em;
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padding: 0 1em 0.25em 0.75em;
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border-left: solid #9999FF 0.25em;
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position: relative;
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z-index: 1;
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}
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.element:before {
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position: absolute;
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z-index: 2;
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top: 0;
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left: -1.15em;
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height: 2em;
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width: 0.9em;
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background: #EEEEFF;
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content: ' ';
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border-style: none none solid solid;
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border-color: #9999FF;
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border-width: 0.25em;
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}
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.example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
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td > .example:only-child { margin: 0 0 0 0.1em; }
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ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
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ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
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ul.domTree li li { list-style: none; }
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ul.domTree li:first-child::before { position: absolute; top: 0; height: 0.6em; left: -0.75em; width: 0.5em; border-style: none none solid solid; content: ''; border-width: 0.1em; }
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ul.domTree li:not(:last-child)::after { position: absolute; top: 0; bottom: -0.6em; left: -0.75em; width: 0.5em; border-style: none none solid solid; content: ''; border-width: 0.1em; }
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ul.domTree span { font-style: italic; font-family: serif; }
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ul.domTree .t1 code { color: purple; font-weight: bold; }
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ul.domTree .t2 { font-style: normal; font-family: monospace; }
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ul.domTree .t2 .name { color: black; font-weight: bold; }
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ul.domTree .t2 .value { color: blue; font-weight: normal; }
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ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
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ul.domTree .t7 code, .domTree .t8 code { color: green; }
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ul.domTree .t10 code { color: teal; }
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body.dfnEnabled dfn { cursor: pointer; }
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.dfnPanel {
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display: inline;
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position: absolute;
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z-index: 10;
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height: auto;
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width: auto;
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padding: 0.5em 0.75em;
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font: small sans-serif, Droid Sans Fallback;
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background: #DDDDDD;
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color: black;
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border: outset 0.2em;
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}
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.dfnPanel * { margin: 0; padding: 0; font: inherit; text-indent: 0; }
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.dfnPanel :link, .dfnPanel :visited { color: black; }
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.dfnPanel p { font-weight: bolder; }
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.dfnPanel * + p { margin-top: 0.25em; }
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.dfnPanel li { list-style-position: inside; }
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#configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
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#configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
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#configUI p label { display: block; }
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#configUI #updateUI, #configUI .loginUI { text-align: center; }
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#configUI input[type=button] { display: block; margin: auto; }
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fieldset { margin: 1em; padding: 0.5em 1em; }
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fieldset > legend + * { margin-top: 0; }
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fieldset > :last-child { margin-bottom: 0; }
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fieldset p { margin: 0.5em 0; }
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.stability {
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position: fixed;
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bottom: 0;
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left: 0; right: 0;
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margin: 0 auto 0 auto !important;
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z-index: 1000;
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width: 50%;
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background: maroon; color: yellow;
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-webkit-border-radius: 1em 1em 0 0;
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-moz-border-radius: 1em 1em 0 0;
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border-radius: 1em 1em 0 0;
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-moz-box-shadow: 0 0 1em #500;
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-webkit-box-shadow: 0 0 1em #500;
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box-shadow: 0 0 1em red;
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padding: 0.5em 1em;
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text-align: center;
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}
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.stability strong {
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display: block;
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}
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.stability input {
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appearance: none; margin: 0; border: 0; padding: 0.25em 0.5em; background: transparent; color: black;
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position: absolute; top: -0.5em; right: 0; font: 1.25em sans-serif; text-align: center;
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}
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.stability input:hover {
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color: white;
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text-shadow: 0 0 2px black;
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}
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.stability input:active {
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padding: 0.3em 0.45em 0.2em 0.55em;
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}
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.stability :link, .stability :visited,
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.stability :link:hover, .stability :visited:hover {
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background: transparent;
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color: white;
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}
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</style><link href="data:text/css,.impl%20%7B%20display:%20none;%20%7D%0Ahtml%20%7B%20border:%20solid%20yellow;%20%7D%20.domintro:before%20%7B%20display:%20none;%20%7D" id="author" rel="alternate stylesheet" title="Author documentation only"><link href="data:text/css,.impl%20%7B%20background:%20%23FFEEEE;%20%7D%20.domintro:before%20%7B%20background:%20%23FFEEEE;%20%7D" id="highlight" rel="alternate stylesheet" title="Highlight implementation
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requirements"><link href="http://www.w3.org/StyleSheets/TR/W3C-WD" rel="stylesheet" type="text/css"><style type="text/css">
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.applies thead th > * { display: block; }
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.applies thead code { display: block; }
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.applies tbody th { whitespace: nowrap; }
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.applies td { text-align: center; }
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.applies .yes { background: yellow; }
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.matrix, .matrix td { border: hidden; text-align: right; }
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.matrix { margin-left: 2em; }
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.dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
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.dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
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.dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
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td.eg { border-width: thin; text-align: center; }
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#table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
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#table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
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#table-example-1 caption { padding-bottom: 0.5em; }
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#table-example-1 thead, #table-example-1 tbody { border: none; }
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#table-example-1 th, #table-example-1 td { border: solid thin; }
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#table-example-1 th { font-weight: normal; }
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#table-example-1 td { border-style: none solid; vertical-align: top; }
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#table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
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#table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
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#table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
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#table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
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#table-example-1 tbody td:first-child::after { content: leader(". "); }
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#table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
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#table-example-1 tbody td:first-child + td { width: 10em; }
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#table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
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#table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
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.apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
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.apple-table-examples * { font-family: "Times", serif; }
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.apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
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.apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
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.apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
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.apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
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.apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
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.apple-table-examples td { text-align: right; vertical-align: top; }
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.apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
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.apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
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.apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
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.apple-table-examples sup { line-height: 0; }
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.details-example img { vertical-align: top; }
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#base64-table {
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white-space: nowrap;
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font-size: 0.6em;
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column-width: 6em;
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column-count: 5;
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column-gap: 1em;
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-moz-column-width: 6em;
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-moz-column-count: 5;
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-moz-column-gap: 1em;
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-webkit-column-width: 6em;
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-webkit-column-count: 5;
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-webkit-column-gap: 1em;
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}
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#base64-table thead { display: none; }
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#base64-table * { border: none; }
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#base64-table tbody td:first-child:after { content: ':'; }
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#base64-table tbody td:last-child { text-align: right; }
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#named-character-references-table {
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white-space: nowrap;
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font-size: 0.6em;
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column-width: 30em;
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column-gap: 1em;
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-moz-column-width: 30em;
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-moz-column-gap: 1em;
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-webkit-column-width: 30em;
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-webkit-column-gap: 1em;
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}
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#named-character-references-table > table > tbody > tr > td:first-child + td,
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#named-character-references-table > table > tbody > tr > td:last-child { text-align: center; }
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#named-character-references-table > table > tbody > tr > td:last-child:hover > span { position: absolute; top: auto; left: auto; margin-left: 0.5em; line-height: 1.2; font-size: 5em; border: outset; padding: 0.25em 0.5em; background: white; width: 1.25em; height: auto; text-align: center; }
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#named-character-references-table > table > tbody > tr#entity-CounterClockwiseContourIntegral > td:first-child { font-size: 0.5em; }
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.glyph.control { color: red; }
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@font-face {
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font-family: 'Essays1743';
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src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743.ttf');
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}
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@font-face {
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font-family: 'Essays1743';
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font-weight: bold;
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src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Bold.ttf');
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}
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@font-face {
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font-family: 'Essays1743';
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font-style: italic;
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src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Italic.ttf');
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}
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@font-face {
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font-family: 'Essays1743';
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font-style: italic;
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font-weight: bold;
|
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src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-BoldItalic.ttf');
|
|
}
|
|
|
|
</style><style type="text/css">
|
|
.domintro:before { display: table; margin: -1em -0.5em -0.5em auto; width: auto; content: 'This box is non-normative. Implementation requirements are given below this box.'; color: black; font-style: italic; border: solid 2px; background: white; padding: 0 0.25em; }
|
|
</style><script type="text/javascript">
|
|
function getCookie(name) {
|
|
var params = location.search.substr(1).split("&");
|
|
for (var index = 0; index < params.length; index++) {
|
|
if (params[index] == name)
|
|
return "1";
|
|
var data = params[index].split("=");
|
|
if (data[0] == name)
|
|
return unescape(data[1]);
|
|
}
|
|
var cookies = document.cookie.split("; ");
|
|
for (var index = 0; index < cookies.length; index++) {
|
|
var data = cookies[index].split("=");
|
|
if (data[0] == name)
|
|
return unescape(data[1]);
|
|
}
|
|
return null;
|
|
}
|
|
</script>
|
|
<script src="link-fixup.js" type="text/javascript"></script>
|
|
<link href="style.css" rel="stylesheet"><link href="semantics.html" title="4 The elements of HTML" rel="prev">
|
|
<link href="spec.html#contents" title="Table of contents" rel="index">
|
|
<link href="sections.html" title="4.4 Sections" rel="next">
|
|
</head><body><div class="head" id="head">
|
|
<div id="multipage-common">
|
|
<p class="stability" id="wip"><strong>This is a work in
|
|
progress!</strong> For the latest updates from the HTML WG, possibly
|
|
including important bug fixes, please look at the <a href="http://dev.w3.org/html5/spec/Overview.html">editor's draft</a> instead.
|
|
There may also be a more
|
|
<a href="http://www.w3.org/TR/html5">up-to-date Working Draft</a>
|
|
with changes based on resolution of Last Call issues.
|
|
<input onclick="closeWarning(this.parentNode)" type="button" value="╳⃝"></p>
|
|
<script type="text/javascript">
|
|
function closeWarning(element) {
|
|
element.parentNode.removeChild(element);
|
|
var date = new Date();
|
|
date.setDate(date.getDate()+4);
|
|
document.cookie = 'hide-obsolescence-warning=1; expires=' + date.toGMTString();
|
|
}
|
|
if (getCookie('hide-obsolescence-warning') == '1')
|
|
setTimeout(function () { document.getElementById('wip').parentNode.removeChild(document.getElementById('wip')); }, 2000);
|
|
</script></div>
|
|
|
|
<p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
|
|
|
|
<h1>HTML5</h1>
|
|
</div><div>
|
|
<a href="semantics.html" class="prev">4 The elements of HTML</a> –
|
|
<a href="spec.html#contents">Table of contents</a> –
|
|
<a href="sections.html" class="next">4.4 Sections</a>
|
|
<ol class="toc"><li><ol><li><a href="scripting-1.html#scripting-1"><span class="secno">4.3 </span>Scripting</a>
|
|
<ol><li><a href="scripting-1.html#the-script-element"><span class="secno">4.3.1 </span>The <code>script</code> element</a>
|
|
<ol><li><a href="scripting-1.html#scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</a></li><li><a href="scripting-1.html#restrictions-for-contents-of-script-elements"><span class="secno">4.3.1.2 </span>Restrictions for contents of <code>script</code> elements</a></li><li><a href="scripting-1.html#inline-documentation-for-external-scripts"><span class="secno">4.3.1.3 </span>Inline documentation for external scripts</a></li><li><a href="scripting-1.html#scriptTagXSLT"><span class="secno">4.3.1.4 </span>Interaction of <code>script</code> elements and XSLT</a></li></ol></li><li><a href="scripting-1.html#the-noscript-element"><span class="secno">4.3.2 </span>The <code>noscript</code> element</a></li></ol></li></ol></li></ol></div>
|
|
|
|
<h3 id="scripting-1"><span class="secno">4.3 </span>Scripting</h3><p>Scripts allow authors to add interactivity to their documents.</p><p>Authors are encouraged to use declarative alternatives to
|
|
scripting where possible, as declarative mechanisms are often more
|
|
maintainable, and many users disable scripting.</p><div class="example">
|
|
<p>For example, instead of using script to show or hide a section
|
|
to show more details, the <code><a href="interactive-elements.html#the-details-element">details</a></code> element could be
|
|
used.</p>
|
|
</div><p>Authors are also encouraged to make their applications degrade
|
|
gracefully in the absence of scripting support.</p><div class="example">
|
|
<p>For example, if an author provides a link in a table header to
|
|
dynamically resort the table, the link could also be made to
|
|
function without scripts by requesting the sorted table from the
|
|
server.</p>
|
|
</div><h4 id="the-script-element"><span class="secno">4.3.1 </span>The <dfn id="script"><code>script</code></dfn> element</h4><dl class="element"><dt>Categories</dt>
|
|
<dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
|
|
<dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
|
|
<dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
|
|
<dt>Contexts in which this element can be used:</dt>
|
|
<dd>Where <a href="content-models.html#metadata-content">metadata content</a> is expected.</dd>
|
|
<dd>Where <a href="content-models.html#phrasing-content">phrasing content</a> is expected.</dd>
|
|
<dt>Content model:</dt>
|
|
<dd>If there is no <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
|
|
attribute, depends on the value of the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, but must match
|
|
<a href="#restrictions-for-contents-of-script-elements">script content restrictions</a>.</dd>
|
|
<dd>If there <em>is</em> a <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
|
|
attribute, the element must be either empty or contain only
|
|
<a href="#inline-documentation-for-external-scripts">script documentation</a> that also matches <a href="#restrictions-for-contents-of-script-elements">script
|
|
content restrictions</a>.</dd>
|
|
<dt>Content attributes:</dt>
|
|
<dd><a href="elements.html#global-attributes">Global attributes</a></dd>
|
|
<dd><code title="attr-script-src"><a href="#attr-script-src">src</a></code></dd>
|
|
<dd><code title="attr-script-async"><a href="#attr-script-async">async</a></code></dd>
|
|
<dd><code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code></dd>
|
|
<dd><code title="attr-script-type"><a href="#attr-script-type">type</a></code></dd>
|
|
<dd><code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code></dd>
|
|
<dt>DOM interface:</dt>
|
|
<dd>
|
|
<pre class="idl">interface <dfn id="htmlscriptelement">HTMLScriptElement</dfn> : <a href="elements.html#htmlelement">HTMLElement</a> {
|
|
attribute DOMString <a href="#dom-script-src" title="dom-script-src">src</a>;
|
|
attribute boolean <a href="#dom-script-async" title="dom-script-async">async</a>;
|
|
attribute boolean <a href="#dom-script-defer" title="dom-script-defer">defer</a>;
|
|
attribute DOMString <a href="#dom-script-type" title="dom-script-type">type</a>;
|
|
attribute DOMString <a href="#dom-script-charset" title="dom-script-charset">charset</a>;
|
|
attribute DOMString <a href="#dom-script-text" title="dom-script-text">text</a>;
|
|
};</pre>
|
|
</dd>
|
|
</dl><p>The <code><a href="#the-script-element">script</a></code> element allows authors to include dynamic
|
|
script and data blocks in their documents. The element does not
|
|
<a href="rendering.html#represents" title="represents">represent</a> content for the user.</p><p>When used to include dynamic scripts, the scripts may either be
|
|
embedded inline or may be imported from an external file using the
|
|
<code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute. If the language
|
|
is not that described by "<code title="">text/javascript</code>",
|
|
then the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute must
|
|
be present, as described below. Whatever language is used, the
|
|
contents of the <code><a href="#the-script-element">script</a></code> element must conform with the
|
|
requirements of that language's specification.</p><p>When used to include data blocks (as opposed to scripts), the
|
|
data must be embedded inline, the format of the data must be given
|
|
using the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, the
|
|
<code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute must not be
|
|
specified, and the contents of the <code><a href="#the-script-element">script</a></code> element must
|
|
conform to the requirements defined for the format used.</p><p>The <dfn id="attr-script-type" title="attr-script-type"><code>type</code></dfn>
|
|
attribute gives the language of the script or format of the data. If
|
|
the attribute is present, its value must be a <a href="infrastructure.html#valid-mime-type">valid MIME
|
|
type</a>. The <code title="">charset</code> parameter must not be
|
|
specified. The default, which is used if the attribute is absent,
|
|
is "<code title="">text/javascript</code>".</p><p>The <dfn id="attr-script-src" title="attr-script-src"><code>src</code></dfn>
|
|
attribute, if specified, gives the address of the external script
|
|
resource to use. The value of the attribute must be a <a href="urls.html#valid-non-empty-url-potentially-surrounded-by-spaces">valid
|
|
non-empty URL potentially surrounded by spaces</a> identifying a
|
|
script resource of the type given by the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, if the attribute is
|
|
present, or of the type "<code title="">text/javascript</code>", if
|
|
the attribute is absent. A resource is a script resource of a given
|
|
type if that type identifies a scripting language and the resource
|
|
conforms with the requirements of that language's specification.</p><p>The <dfn id="attr-script-charset" title="attr-script-charset"><code>charset</code></dfn>
|
|
attribute gives the character encoding of the external script
|
|
resource. The attribute must not be specified if the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is not present. If the
|
|
attribute is set, its value must be a valid character encoding name,
|
|
must be an <a href="infrastructure.html#ascii-case-insensitive">ASCII case-insensitive</a> match for the
|
|
<a href="infrastructure.html#preferred-mime-name">preferred MIME name</a> for that encoding, and must match
|
|
the encoding given in the <code title="">charset</code> parameter of
|
|
the <a href="fetching-resources.html#content-type" title="Content-Type">Content-Type metadata</a> of the
|
|
external file, if any. <a href="references.html#refsIANACHARSET">[IANACHARSET]</a></p><p>The <dfn id="attr-script-async" title="attr-script-async"><code>async</code></dfn> and
|
|
<dfn id="attr-script-defer" title="attr-script-defer"><code>defer</code></dfn> attributes
|
|
are <a href="common-microsyntaxes.html#boolean-attribute" title="boolean attribute">boolean attributes</a> that
|
|
indicate how the script should be executed. The <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> and <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attributes must not be
|
|
specified if the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute
|
|
is not present.</p><p>There are three possible modes that can be selected using these
|
|
attributes. If the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
|
|
attribute is present, then the script will be executed
|
|
asynchronously, as soon as it is available. If the <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute is not present but
|
|
the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute is
|
|
present, then the script is executed when the page has finished
|
|
parsing. If neither attribute is present, then the script is
|
|
fetched and executed immediately, before the user agent continues
|
|
parsing the page.</p><p class="note">The exact processing details for these attributes
|
|
are, for mostly historical reasons, somewhat non-trivial, involving
|
|
a number of aspects of HTML. The implementation requirements are
|
|
therefore by necessity scattered throughout the specification. The
|
|
algorithms below (in this section) describe the core of this
|
|
processing, but these algorithms reference and are referenced by the
|
|
parsing rules for <code><a href="#the-script-element">script</a></code> <a href="tree-construction.html#scriptTag">start</a>
|
|
and <a href="tree-construction.html#scriptEndTag">end</a> tags in HTML, <a href="tree-construction.html#scriptForeignEndTag">in foreign content</a>, and <a href="the-xhtml-syntax.html#scriptTagXML">in XML</a>, the rules for the <code title="dom-document-write"><a href="apis-in-html-documents.html#dom-document-write">document.write()</a></code> method, the
|
|
handling of <a href="webappapis.html#scripting">scripting</a>, etc.</p><p>The <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute may be
|
|
specified even if the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
|
|
attribute is specified, to cause legacy Web browsers that only
|
|
support <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> (and not <code title="attr-script-async"><a href="#attr-script-async">async</a></code>) to fall back to the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> behavior instead of the
|
|
synchronous blocking behavior that is the default.</p><p>Changing the <code title="attr-script-src"><a href="#attr-script-src">src</a></code>, <code title="attr-script-type"><a href="#attr-script-type">type</a></code>, <code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code>, <code title="attr-script-async"><a href="#attr-script-async">async</a></code>, and <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attributes dynamically has no
|
|
direct effect; these attribute are only used at specific times
|
|
described below.</p><div class="impl">
|
|
|
|
<p>A <code><a href="#the-script-element">script</a></code> element has several associated pieces of
|
|
state.</p>
|
|
|
|
<p>The first is a flag indicating whether or not the script block
|
|
has been <dfn id="already-started">"already started"</dfn>. Initially,
|
|
<code><a href="#the-script-element">script</a></code> elements must have this flag unset (script
|
|
blocks, when created, are not "already started"). When a
|
|
<code><a href="#the-script-element">script</a></code> element is <a href="infrastructure.html#concept-clone" title="concept-clone">cloned</a>, the "already started" flag, if
|
|
set, must be propagated to the clone when it is created.</p>
|
|
|
|
<p>The second is a flag indicating whether the element was
|
|
<dfn id="parser-inserted">"parser-inserted"</dfn>. Initially, <code><a href="#the-script-element">script</a></code>
|
|
elements must have this flag unset. It is set by the <a href="parsing.html#html-parser">HTML
|
|
parser</a> and the <a href="the-xhtml-syntax.html#xml-parser">XML parser</a> on <code><a href="#the-script-element">script</a></code>
|
|
elements they insert and affects the processing of those
|
|
elements.</p>
|
|
|
|
<p>The third is a flag indicating whether the element will
|
|
<dfn id="force-async">"force-async"</dfn>. Initially, <code><a href="#the-script-element">script</a></code> elements
|
|
must have this flag set. It is unset by the <a href="parsing.html#html-parser">HTML parser</a>
|
|
and the <a href="the-xhtml-syntax.html#xml-parser">XML parser</a> on <code><a href="#the-script-element">script</a></code> elements they
|
|
insert. In addition, whenever a <code><a href="#the-script-element">script</a></code> element whose
|
|
<a href="#force-async">"force-async"</a> flag is set has a <code title="attr-script-async"><a href="#attr-script-async">async</a></code> content attribute added, the
|
|
element's <a href="#force-async">"force-async"</a> flag must be unset.</p>
|
|
<p>The fourth is a flag indicating whether or not the script block is
|
|
<dfn id="ready-to-be-parser-executed">"ready to be parser-executed"</dfn>. Initially,
|
|
<code><a href="#the-script-element">script</a></code> elements must have this flag unset (script
|
|
blocks, when created, are not "ready to be parser-executed"). This
|
|
flag is used only for elements that are also
|
|
<a href="#parser-inserted">"parser-inserted"</a>, to let the parser know when to
|
|
execute the script.</p>
|
|
|
|
<p>The last few pieces of state are <dfn id="the-script-block-s-type"><var>the script block's
|
|
type</var></dfn>, <dfn id="the-script-block-s-character-encoding"><var>the script block's character
|
|
encoding</var></dfn>, and <dfn id="the-script-block-s-fallback-character-encoding"><var>the script block's fallback
|
|
character encoding</var></dfn>. They are determined when the script
|
|
is prepared, based on the attributes on the element at that time,
|
|
and the <code><a href="infrastructure.html#document">Document</a></code> of the <code><a href="#the-script-element">script</a></code>
|
|
element.</p>
|
|
|
|
<p>When a <code><a href="#the-script-element">script</a></code> element that is not marked as being
|
|
<a href="#parser-inserted">"parser-inserted"</a> experiences one of the events listed
|
|
in the following list, the user agent must synchronously <a href="#prepare-a-script" title="prepare a script">prepare</a> the <code><a href="#the-script-element">script</a></code>
|
|
element:</p>
|
|
|
|
<ul><li>The <code><a href="#the-script-element">script</a></code> element gets <a href="infrastructure.html#insert-an-element-into-a-document" title="insert an
|
|
element into a document">inserted into a document</a>.</li>
|
|
|
|
<li>The <code><a href="#the-script-element">script</a></code> element is <a href="infrastructure.html#in-a-document">in a
|
|
<code>Document</code></a> and its child nodes are changed.</li>
|
|
|
|
<li>The <code><a href="#the-script-element">script</a></code> element is <a href="infrastructure.html#in-a-document">in a
|
|
<code>Document</code></a> and has a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute set where previously
|
|
the element had no such attribute.</li>
|
|
|
|
</ul><p>To <dfn id="prepare-a-script" title="prepare a script">prepare a script</dfn>, the user
|
|
agent must act as follows:</p>
|
|
|
|
<ol><li>
|
|
|
|
<p>If the <code><a href="#the-script-element">script</a></code> element is marked as having
|
|
<a href="#already-started">"already started"</a>, then the user agent must abort
|
|
these steps at this point. The script is not executed.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If the element has its <a href="#parser-inserted">"parser-inserted"</a> flag set,
|
|
then set <var title="">was-parser-inserted</var> to true and unset
|
|
the element's <a href="#parser-inserted">"parser-inserted"</a> flag. Otherwise, set
|
|
<var title="">was-parser-inserted</var> to false.</p>
|
|
|
|
<p class="note">This is done so that if parser-inserted
|
|
<code><a href="#the-script-element">script</a></code> elements fail to run when the parser tries to
|
|
run them, e.g. because they are empty or specify an unsupported
|
|
scripting language, another script can later mutate them and cause
|
|
them to run again.</p>
|
|
|
|
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If <var title="">was-parser-inserted</var> is true and the
|
|
element does not have an <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute, then set the
|
|
element's <a href="#force-async">"force-async"</a> flag to true.</p>
|
|
|
|
<p class="note">This is done so that if a parser-inserted
|
|
<code><a href="#the-script-element">script</a></code> element fails to run when the parser tries to
|
|
run it, but it is later executed after a script dynamically
|
|
updates it, it will execute asynchronously even if the
|
|
<code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute isn't
|
|
set.</p>
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-empty">
|
|
|
|
<p>If the element has no <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
|
|
attribute, and its child nodes, if any, consist only of comment
|
|
nodes and empty <a href="infrastructure.html#text-node" title="text node">text nodes</a>, then
|
|
the user agent must abort these steps at this point. The script is
|
|
not executed.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If the element is not <a href="infrastructure.html#in-a-document">in a <code>Document</code></a>,
|
|
then the user agent must abort these steps at this point. The
|
|
script is not executed.</p>
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-prepare">
|
|
|
|
<p>If either:</p>
|
|
|
|
<ul class="brief"><li>the <code><a href="#the-script-element">script</a></code> element has a <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute and its value is
|
|
the empty string, or</li>
|
|
|
|
<li>the <code><a href="#the-script-element">script</a></code> element has no <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute but it has a <code title="attr-script-language"><a href="obsolete.html#attr-script-language">language</a></code> attribute and
|
|
<em>that</em> attribute's value is the empty string, or</li>
|
|
|
|
<li>the <code><a href="#the-script-element">script</a></code> element has neither a <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute nor a <code title="attr-script-language"><a href="obsolete.html#attr-script-language">language</a></code> attribute, then</li>
|
|
|
|
</ul><p>...let <var><a href="#the-script-block-s-type">the script block's type</a></var> for this
|
|
<code><a href="#the-script-element">script</a></code> element be "<code title="">text/javascript</code>".</p>
|
|
|
|
<p>Otherwise, if the <code><a href="#the-script-element">script</a></code> element has a <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, let <var><a href="#the-script-block-s-type">the
|
|
script block's type</a></var> for this <code><a href="#the-script-element">script</a></code> element be
|
|
the value of that attribute with any leading or trailing sequences
|
|
of <a href="common-microsyntaxes.html#space-character" title="space character">space characters</a>
|
|
removed.</p>
|
|
|
|
<p>Otherwise, the element has a non-empty <code title="attr-script-language"><a href="obsolete.html#attr-script-language">language</a></code> attribute; let
|
|
<var><a href="#the-script-block-s-type">the script block's type</a></var> for this <code><a href="#the-script-element">script</a></code>
|
|
element be the concatenation of the string "<code title="">text/</code>" followed by the value of the <code title="attr-script-language"><a href="obsolete.html#attr-script-language">language</a></code> attribute.</p>
|
|
<p class="note">The <code title="attr-script-language"><a href="obsolete.html#attr-script-language">language</a></code> attribute is never
|
|
conforming, and is always ignored if there is a <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute present.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If the user agent does not <a href="#support-the-scripting-language">support the scripting
|
|
language</a> given by <var><a href="#the-script-block-s-type">the script block's type</a></var> for
|
|
this <code><a href="#the-script-element">script</a></code> element, then the user agent must abort
|
|
these steps at this point. The script is not executed.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If <var title="">was-parser-inserted</var> is true, then flag
|
|
the element as <a href="#parser-inserted">"parser-inserted"</a> again, and set the
|
|
element's <a href="#force-async">"force-async"</a> flag to false.</p>
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-start">
|
|
|
|
<p>The user agent must set the element's <a href="#already-started">"already
|
|
started"</a> flag.</p>
|
|
|
|
<p class="note">The state of the element at this moment <a href="#establish-script-block-source">is later used</a> to
|
|
determine the script source.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If the element is flagged as <a href="#parser-inserted">"parser-inserted"</a>,
|
|
but the element's <code><a href="infrastructure.html#document">Document</a></code> is not the
|
|
<code><a href="infrastructure.html#document">Document</a></code> of the parser that created the element, then
|
|
abort these steps.</p>
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-noscript">
|
|
|
|
<p>If <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is
|
|
disabled</a> for the <code><a href="#the-script-element">script</a></code> element, then the user
|
|
agent must abort these steps at this point. The script is not
|
|
executed.</p>
|
|
|
|
<p class="note">The definition of <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> means
|
|
that, amongst others, the following scripts will not execute:
|
|
scripts in <code>XMLHttpRequest</code>'s <code title="dom-XMLHttpRequest-responseXML">responseXML</code>
|
|
documents, scripts in <code>DOMParser</code>-created documents,
|
|
scripts in documents created by <code>XSLTProcessor</code>'s <code title="dom-XSLTProcessor-transformToDocument">transformToDocument</code>
|
|
feature, and scripts that are first inserted by a script into a
|
|
<code><a href="infrastructure.html#document">Document</a></code> that was created using the <code title="dom-DOMImplementation-createDocument"><a href="infrastructure.html#dom-domimplementation-createdocument">createDocument()</a></code>
|
|
API. <a href="references.html#refsXHR">[XHR]</a> <a href="references.html#refsDOMPARSER">[DOMPARSER]</a> <a href="references.html#refsDOMCORE">[DOMCORE]</a></p>
|
|
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-for">
|
|
|
|
<p>If the <code><a href="#the-script-element">script</a></code> element has an <code title="attr-script-event"><a href="obsolete.html#attr-script-event">event</a></code> attribute and a <code title="attr-script-for"><a href="obsolete.html#attr-script-for">for</a></code> attribute, then run these
|
|
substeps:</p>
|
|
|
|
<ol><li><p>Let <var title="">for</var> be the value of the <code title="attr-script-for"><a href="obsolete.html#attr-script-for">for</a></code> attribute.</p></li>
|
|
|
|
<li><p>Let <var title="">event</var> be the value of the <code title="attr-script-event"><a href="obsolete.html#attr-script-event">event</a></code> attribute.</p></li>
|
|
|
|
<li><p><a href="common-microsyntaxes.html#strip-leading-and-trailing-whitespace">Strip leading and trailing whitespace</a> from
|
|
<var title="">event</var> and <var title="">for</var>.</p></li>
|
|
|
|
<li><p>If <var title="">for</var> is not an <a href="infrastructure.html#ascii-case-insensitive">ASCII
|
|
case-insensitive</a> match for the string "<code title="">window</code>", then the user agent must abort these
|
|
steps at this point. The script is not executed.</p></li>
|
|
|
|
<li><p>If <var title="">event</var> is not an <a href="infrastructure.html#ascii-case-insensitive">ASCII
|
|
case-insensitive</a> match for either the string "<code title="">onload</code>" or the string "<code title="">onload()</code>", then the user agent must abort these
|
|
steps at this point. The script is not executed.</p></li>
|
|
|
|
</ol></li>
|
|
|
|
<li id="script-processing-encoding">
|
|
|
|
<p>If the <code><a href="#the-script-element">script</a></code> element has a <code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code> attribute, then let
|
|
<var><a href="#the-script-block-s-character-encoding">the script block's character encoding</a></var> for this
|
|
<code><a href="#the-script-element">script</a></code> element be the encoding given by the <code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code> attribute.</p>
|
|
|
|
<p>Otherwise, let <var><a href="#the-script-block-s-fallback-character-encoding">the script block's fallback character
|
|
encoding</a></var> for this <code><a href="#the-script-element">script</a></code> element be the same as
|
|
<a href="dom.html#document-s-character-encoding" title="document's character encoding">the encoding of the
|
|
document itself</a>.</p>
|
|
|
|
<p class="note">Only one of these two pieces of state is set.</p>
|
|
|
|
</li>
|
|
|
|
<li id="script-processing-src-prepare">
|
|
|
|
<p>If the element has a <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
|
|
attribute whose value is not the empty string, then the value of
|
|
that attribute must be <a href="urls.html#resolve-a-url" title="resolve a url">resolved</a>
|
|
relative to the element, and if that is successful, the specified
|
|
resource must then be <a href="fetching-resources.html#fetch" title="fetch">fetched</a>, from the
|
|
<a href="origin-0.html#origin">origin</a> of the element's <code><a href="infrastructure.html#document">Document</a></code>.</p>
|
|
|
|
|
|
<p>If the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute's
|
|
value is the empty string or if it could not be resolved, then the
|
|
user agent must <a href="webappapis.html#queue-a-task">queue a task</a> to <a href="webappapis.html#fire-a-simple-event">fire a simple
|
|
event</a> named <code title="event-error">error</code> at the
|
|
element, and abort these steps.</p>
|
|
|
|
<p>For historical reasons, if the <a href="urls.html#url">URL</a> is a <a href="webappapis.html#javascript-protocol" title="javascript protocol"><code title="">javascript:</code>
|
|
URL</a>, then the user agent must not, despite the requirements
|
|
in the definition of the <a href="fetching-resources.html#fetch" title="fetch">fetching</a>
|
|
algorithm, actually execute the script in the URL; instead the
|
|
user agent must act as if it had received an empty HTTP 400
|
|
response.</p>
|
|
|
|
<p>For performance reasons, user agents may start fetching the
|
|
script as soon as the attribute is set, instead, in the hope that
|
|
the element will be inserted into the document. Either way, once
|
|
the element is <a href="infrastructure.html#insert-an-element-into-a-document" title="insert an element into a
|
|
document">inserted into the document</a>, the load must have
|
|
started. If the UA performs such prefetching, but the element is
|
|
never inserted in the document, or the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is dynamically
|
|
changed, then the
|
|
user agent will not execute the script, and the fetching process
|
|
will have been effectively wasted.</p>
|
|
|
|
</li>
|
|
|
|
|
|
<li>
|
|
|
|
<p>Then, the first of the following options that describes the
|
|
situation must be followed:</p>
|
|
|
|
<dl class="switch"><dt id="script-processing-defer">If the element has a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute, and the element has
|
|
a <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute, and the
|
|
element has been flagged as <a href="#parser-inserted">"parser-inserted"</a>, and
|
|
the element does not have an <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The element must be added to the end of the <dfn id="list-of-scripts-that-will-execute-when-the-document-has-finished-parsing">list of
|
|
scripts that will execute when the document has finished
|
|
parsing</dfn> associated with the <code><a href="infrastructure.html#document">Document</a></code> of the
|
|
parser that created the element.</p>
|
|
|
|
<p>The <a href="webappapis.html#concept-task" title="concept-task">task</a> that the
|
|
<a href="webappapis.html#networking-task-source">networking task source</a> places on the <a href="webappapis.html#task-queue">task
|
|
queue</a> once the <a href="fetching-resources.html#fetch" title="fetch">fetching
|
|
algorithm</a> has completed must set the element's
|
|
<a href="#ready-to-be-parser-executed">"ready to be parser-executed"</a> flag. The parser will
|
|
handle executing the script.</p>
|
|
|
|
</dd>
|
|
|
|
|
|
<dt id="script-processing-parser-inserted">If the element has a
|
|
<code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute, and the
|
|
element has been flagged as <a href="#parser-inserted">"parser-inserted"</a>, and
|
|
the element does not have an <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The element is the <a href="#pending-parsing-blocking-script">pending parsing-blocking
|
|
script</a> of the <code><a href="infrastructure.html#document">Document</a></code> of the parser that
|
|
created the element. (There can only be one such script per
|
|
<code><a href="infrastructure.html#document">Document</a></code> at a time.)</p>
|
|
|
|
<p>The <a href="webappapis.html#concept-task" title="concept-task">task</a> that the
|
|
<a href="webappapis.html#networking-task-source">networking task source</a> places on the <a href="webappapis.html#task-queue">task
|
|
queue</a> once the <a href="fetching-resources.html#fetch" title="fetch">fetching
|
|
algorithm</a> has completed must set the element's
|
|
<a href="#ready-to-be-parser-executed">"ready to be parser-executed"</a> flag. The parser will
|
|
handle executing the script.</p>
|
|
|
|
</dd>
|
|
|
|
|
|
<dt id="script-processing-style-delayed">If the element does not
|
|
have a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute, and
|
|
the element has been flagged as <a href="#parser-inserted">"parser-inserted"</a>,
|
|
and the <code><a href="infrastructure.html#document">Document</a></code> of the <a href="parsing.html#html-parser">HTML parser</a> or
|
|
<a href="the-xhtml-syntax.html#xml-parser">XML parser</a> that created the <code><a href="#the-script-element">script</a></code>
|
|
element <a href="semantics.html#has-a-style-sheet-that-is-blocking-scripts">has a style sheet that is blocking
|
|
scripts</a></dt>
|
|
|
|
<dd>
|
|
|
|
<p>The element is the <a href="#pending-parsing-blocking-script">pending parsing-blocking
|
|
script</a> of the <code><a href="infrastructure.html#document">Document</a></code> of the parser that
|
|
created the element. (There can only be one such script per
|
|
<code><a href="infrastructure.html#document">Document</a></code> at a time.)</p>
|
|
|
|
<p>Set the element's <a href="#ready-to-be-parser-executed">"ready to be parser-executed"</a>
|
|
flag. The parser will handle executing the script.</p>
|
|
|
|
</dd>
|
|
|
|
|
|
<dt id="script-processing-src-sync">If the element has a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute, does not have an
|
|
<code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute, and does
|
|
not have the <a href="#force-async">"force-async"</a> flag set</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The element must be added to the end of the <dfn id="list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of
|
|
scripts that will execute in order as soon as possible</dfn>
|
|
associated with the <code><a href="infrastructure.html#document">Document</a></code> of the
|
|
<code><a href="#the-script-element">script</a></code> element at the time the <a href="#prepare-a-script">prepare a
|
|
script</a> algorithm started.</p>
|
|
|
|
<p>The <a href="webappapis.html#concept-task" title="concept-task">task</a> that the
|
|
<a href="webappapis.html#networking-task-source">networking task source</a> places on the <a href="webappapis.html#task-queue">task
|
|
queue</a> once the <a href="fetching-resources.html#fetch" title="fetch">fetching
|
|
algorithm</a> has completed must run the following steps:</p>
|
|
|
|
<ol><li><p>If the element is not now the first element in the
|
|
<a href="#list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of scripts that will execute in order as soon as
|
|
possible</a> to which it was added above, then mark the
|
|
element as ready but abort these steps without executing the
|
|
script yet.</p></li>
|
|
|
|
<li><p><i>Execution</i>: <a href="#execute-the-script-block">Execute the script block</a>
|
|
corresponding to the first script element in this <a href="#list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of
|
|
scripts that will execute in order as soon as
|
|
possible</a>.</p></li>
|
|
|
|
<li><p>Remove the first element from this <a href="#list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of scripts
|
|
that will execute in order as soon as possible</a>.</p></li>
|
|
|
|
<li><p>If this <a href="#list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of scripts that will execute in order
|
|
as soon as possible</a> is still not empty and the first
|
|
entry has already been marked as ready, then jump back to the
|
|
step labeled <i>execution</i>.</p></li>
|
|
|
|
</ol></dd>
|
|
|
|
|
|
<dt id="script-processing-src">If the element has a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The element must be added to the <dfn id="set-of-scripts-that-will-execute-as-soon-as-possible">set of scripts that
|
|
will execute as soon as possible</dfn> of the
|
|
<code><a href="infrastructure.html#document">Document</a></code> of the <code><a href="#the-script-element">script</a></code> element at the
|
|
time the <a href="#prepare-a-script">prepare a script</a> algorithm started.</p>
|
|
|
|
<p>The <a href="webappapis.html#concept-task" title="concept-task">task</a> that the
|
|
<a href="webappapis.html#networking-task-source">networking task source</a> places on the <a href="webappapis.html#task-queue">task
|
|
queue</a> once the <a href="fetching-resources.html#fetch" title="fetch">fetching
|
|
algorithm</a> has completed must <a href="#execute-the-script-block">execute the script
|
|
block</a> and then remove the element from the <a href="#set-of-scripts-that-will-execute-as-soon-as-possible">set of
|
|
scripts that will execute as soon as possible</a>.</p>
|
|
|
|
</dd>
|
|
|
|
|
|
<dt id="script-processing-inline">Otherwise</dt>
|
|
|
|
<dd>The user agent must immediately <a href="#execute-the-script-block">execute the script
|
|
block</a>, even if other scripts are already executing.</dd>
|
|
|
|
</dl></li>
|
|
|
|
</ol><p>Fetching an external script must <a href="the-end.html#delay-the-load-event">delay the load
|
|
event</a> of the element's document until the <a href="webappapis.html#concept-task" title="concept-task">task</a> that is <a href="webappapis.html#queue-a-task" title="queue a
|
|
task">queued</a> by the <a href="webappapis.html#networking-task-source">networking task source</a> once
|
|
the resource has been <a href="fetching-resources.html#fetch" title="fetch">fetched</a> (defined
|
|
above) has been run.</p>
|
|
|
|
<p>The <dfn id="pending-parsing-blocking-script">pending parsing-blocking script</dfn> of a
|
|
<code><a href="infrastructure.html#document">Document</a></code> is used by the <code><a href="infrastructure.html#document">Document</a></code>'s
|
|
parser(s).</p>
|
|
|
|
<p class="note">If a <code><a href="#the-script-element">script</a></code> element that blocks a
|
|
parser gets moved to another <code><a href="infrastructure.html#document">Document</a></code> before it would
|
|
normally have stopped blocking that parser, it nonetheless continues
|
|
blocking that parser until the condition that causes it to be
|
|
blocking the parser no longer applies (e.g. if the script is a
|
|
<a href="#pending-parsing-blocking-script">pending parsing-blocking script</a> because there was
|
|
<a href="semantics.html#a-style-sheet-that-is-blocking-scripts">a style sheet that is blocking scripts</a> when it was
|
|
parsed, but then the script is moved to another
|
|
<code><a href="infrastructure.html#document">Document</a></code> before the style sheet loads, the script still
|
|
blocks the parser until the style sheets are all loaded, at which
|
|
time the script executes and the parser is unblocked).</p>
|
|
|
|
|
|
<p>When the user agent is required to <dfn id="execute-the-script-block" title="execute the script
|
|
block">execute a script block</dfn>, it must run the following
|
|
steps:</p>
|
|
|
|
<ol><li>
|
|
|
|
<p>If the element is flagged as <a href="#parser-inserted">"parser-inserted"</a>,
|
|
but the element's <code><a href="infrastructure.html#document">Document</a></code> is not the
|
|
<code><a href="infrastructure.html#document">Document</a></code> of the parser that created the element, then
|
|
abort these steps.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>Jump to the appropriate set of steps from the list below:</p>
|
|
|
|
<dl class="switch"><dt>If the load resulted in an error (for example a DNS error, or
|
|
an HTTP 404 error)</dt>
|
|
|
|
<dd><p>Executing the script block must just consist of <a href="webappapis.html#fire-a-simple-event" title="fire a simple event">firing a simple event</a> named
|
|
<code title="event-error">error</code> at the element.</p></dd>
|
|
|
|
<dt>If the load was successful</dt>
|
|
|
|
<!-- SCRIPT EXEC -->
|
|
<dd>
|
|
|
|
<p>Executing the script block must consist of running the
|
|
following steps. For the purposes of these steps, the script is
|
|
considered to be from an <i>external file</i> if, while the
|
|
<a href="#prepare-a-script">prepare a script</a> algorithm above was running for
|
|
this script, the <code><a href="#the-script-element">script</a></code> element had a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute specified.</p>
|
|
|
|
<ol><li id="establish-script-block-source">
|
|
|
|
<p>Initialize <dfn id="the-script-block-s-source"><var>the script block's source</var></dfn>
|
|
as follows:</p>
|
|
|
|
<dl class="switch"><dt>If the script is from an external file and <var><a href="#the-script-block-s-type">the
|
|
script block's type</a></var> is a text-based language</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The contents of that file, interpreted as string of
|
|
Unicode characters, are the script source.</p>
|
|
|
|
<p>To obtain the string of Unicode characters, the user
|
|
agent run the following steps:</p>
|
|
|
|
<ol><li><p>If the resource's <a href="fetching-resources.html#content-type" title="Content-Type">Content
|
|
Type metadata</a>, if any, specifies a character
|
|
encoding, and the user agent supports that encoding, then
|
|
let <var title="">character encoding</var> be that
|
|
encoding, and jump to the bottom step in this series of
|
|
steps.</p></li>
|
|
|
|
<li><p>If the algorithm above set <var><a href="#the-script-block-s-character-encoding">the script block's
|
|
character encoding</a></var>, then let <var title="">character
|
|
encoding</var> be that encoding, and jump to the bottom
|
|
step in this series of steps.</p></li>
|
|
|
|
<li><p>For each of the rows in the following table,
|
|
starting with the first one and going down, if the file has
|
|
as many or more bytes available than the number of bytes in
|
|
the first column, and the first bytes of the file match the
|
|
bytes given in the first column, then set <var title="">character encoding</var> to the encoding given in
|
|
the cell in the second column of that row, and jump to the
|
|
bottom step in this series of steps:</p>
|
|
|
|
|
|
<table id="table-script-bom"><thead><tr><th>Bytes in Hexadecimal
|
|
</th><th>Encoding
|
|
</th></tr></thead><tbody><tr><td>FE FF
|
|
</td><td>Big-endian UTF-16
|
|
</td></tr><tr><td>FF FE
|
|
</td><td>Little-endian UTF-16
|
|
</td></tr><tr><td>EF BB BF
|
|
</td><td>UTF-8
|
|
</td></tr></tbody></table><p class="note">This step looks for Unicode Byte Order
|
|
Marks (BOMs).</p>
|
|
|
|
</li>
|
|
|
|
<li><p>Let <var title="">character encoding</var> be
|
|
<var><a href="#the-script-block-s-fallback-character-encoding">the script block's fallback character
|
|
encoding</a></var>.</p></li>
|
|
|
|
<li><p>Convert the file to Unicode using <var>character
|
|
encoding</var>, following the rules for doing so given by
|
|
the specification for <var><a href="#the-script-block-s-type">the script block's
|
|
type</a></var>.</p></li>
|
|
|
|
</ol></dd>
|
|
|
|
<dt>If the script is from an external file and <var><a href="#the-script-block-s-type">the
|
|
script block's type</a></var> is an XML-based language</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The external file is the script source. When it is later
|
|
executed, it must be interpreted in a manner consistent with
|
|
the specification defining the language given by <var><a href="#the-script-block-s-type">the
|
|
script block's type</a></var>.</p>
|
|
|
|
</dd>
|
|
|
|
<dt>If the script is inline and <var><a href="#the-script-block-s-type">the script block's
|
|
type</a></var> is a text-based language</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The value of the <code title="dom-script-text"><a href="#dom-script-text">text</a></code> IDL attribute at the
|
|
time the element's <a href="#already-started">"already started"</a> flag was
|
|
last set is the script source.</p>
|
|
|
|
</dd>
|
|
|
|
<dt>If the script is inline and <var><a href="#the-script-block-s-type">the script block's
|
|
type</a></var> is an XML-based language</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The child nodes of the <code><a href="#the-script-element">script</a></code> element at the
|
|
time the element's <a href="#already-started">"already started"</a> flag was
|
|
last set are the script source.</p>
|
|
|
|
</dd>
|
|
|
|
</dl></li>
|
|
|
|
<li>
|
|
|
|
<p>If the script is from an external file, then increment the
|
|
<a href="apis-in-html-documents.html#ignore-destructive-writes-counter">ignore-destructive-writes counter</a> of the
|
|
<code><a href="#the-script-element">script</a></code> element's <code><a href="infrastructure.html#document">Document</a></code>. Let <var title="">neutralized doc</var> be that
|
|
<code><a href="infrastructure.html#document">Document</a></code>.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p><a href="webappapis.html#create-a-script-from-a-node" title="create a script from a node">Create a
|
|
script</a> from the <code><a href="#the-script-element">script</a></code> element node, using
|
|
<var><a href="#the-script-block-s-source">the script block's source</a></var> and <var><a href="#the-script-block-s-type">the script
|
|
block's type</a></var>.</p>
|
|
|
|
<p class="note">This is where the script is compiled and
|
|
actually executed.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>Decrement the <a href="apis-in-html-documents.html#ignore-destructive-writes-counter">ignore-destructive-writes
|
|
counter</a> of <var title="">neutralized doc</var>, if it
|
|
was incremented in the earlier step.</p>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
|
|
<p>If the script is from an external file, <a href="webappapis.html#fire-a-simple-event">fire a simple
|
|
event</a> named <code title="event-load">load</code> at the
|
|
<code><a href="#the-script-element">script</a></code> element.</p>
|
|
|
|
<p>Otherwise, the script is internal; <a href="webappapis.html#queue-a-task">queue a
|
|
task</a> to <a href="webappapis.html#fire-a-simple-event">fire a simple event</a> named <code title="event-load">load</code> at the <code><a href="#the-script-element">script</a></code>
|
|
element.</p>
|
|
|
|
</li>
|
|
|
|
</ol></dd>
|
|
|
|
</dl></li>
|
|
|
|
</ol><p>The IDL attributes <dfn id="dom-script-src" title="dom-script-src"><code>src</code></dfn>, <dfn id="dom-script-type" title="dom-script-type"><code>type</code></dfn>, <dfn id="dom-script-charset" title="dom-script-charset"><code>charset</code></dfn>, and <dfn id="dom-script-defer" title="dom-script-defer"><code>defer</code></dfn>, each must
|
|
<a href="common-dom-interfaces.html#reflect">reflect</a> the respective content attributes of the same
|
|
name.</p>
|
|
|
|
<p>The <dfn id="dom-script-async" title="dom-script-async"><code>async</code></dfn> IDL
|
|
attribute controls whether the element will execute asynchronously
|
|
or not. If the element's <a href="#force-async">"force-async"</a> flag is set,
|
|
then, on getting, the <code title="dom-script-async"><a href="#dom-script-async">async</a></code>
|
|
IDL attribute must return true, and on setting, the
|
|
<a href="#force-async">"force-async"</a> flag must first be unset, and then the
|
|
content attribute must be removed if the IDL attribute's new value
|
|
is false, and must be set to the empty string if the IDL attribute's
|
|
new value is true. If the element's <a href="#force-async">"force-async"</a> flag
|
|
is <em>not</em> set, the IDL attribute must <a href="common-dom-interfaces.html#reflect">reflect</a> the
|
|
<code title="attr-script-async"><a href="#attr-script-async">async</a></code> content attribute.</p>
|
|
|
|
</div><dl class="domintro"><dt><var title="">script</var> . <code title="dom-script-text"><a href="#dom-script-text">text</a></code> [ = <var title="">value</var> ]</dt>
|
|
|
|
<dd>
|
|
|
|
<p>Returns the contents of the element, ignoring child nodes that
|
|
aren't <a href="infrastructure.html#text-node" title="text node">text nodes</a>.</p>
|
|
|
|
<p>Can be set, to replace the element's children with the given
|
|
value.</p>
|
|
|
|
</dd>
|
|
|
|
</dl><div class="impl">
|
|
|
|
<p>The IDL attribute <dfn id="dom-script-text" title="dom-script-text"><code>text</code></dfn> must return a
|
|
concatenation of the contents of all the <a href="infrastructure.html#text-node" title="text
|
|
node">text nodes</a> that are direct children of the
|
|
<code><a href="#the-script-element">script</a></code> element (ignoring any other nodes such as
|
|
comments or elements), in tree order. On setting, it must act the
|
|
same way as the <code><a href="infrastructure.html#textcontent">textContent</a></code> IDL attribute.</p>
|
|
|
|
</div><p class="note">When inserted using the <code title="dom-document-write"><a href="apis-in-html-documents.html#dom-document-write">document.write()</a></code> method,
|
|
<code><a href="#the-script-element">script</a></code> elements execute (typically synchronously), but
|
|
when inserted using <code title="dom-innerHTML"><a href="apis-in-html-documents.html#dom-innerhtml">innerHTML</a></code> and <code title="dom-outerHTML"><a href="apis-in-html-documents.html#dom-outerhtml">outerHTML</a></code> attributes, they do not
|
|
execute at all.</p><div class="example">
|
|
|
|
<p>In this example, two <code><a href="#the-script-element">script</a></code> elements are used. One
|
|
embeds an external script, and the other includes some data.</p>
|
|
|
|
<pre><script src="game-engine.js"></script>
|
|
<script type="text/x-game-map">
|
|
........U.........e
|
|
o............A....e
|
|
.....A.....AAA....e
|
|
.A..AAA...AAAAA...e
|
|
</script></pre>
|
|
|
|
<p>The data in this case might be used by the script to generate
|
|
the map of a video game. The data doesn't have to be used that way,
|
|
though; maybe the map data is actually embedded in other parts of
|
|
the page's markup, and the data block here is just used by the
|
|
site's search engine to help users who are looking for particular
|
|
features in their game maps.</p>
|
|
|
|
</div><div class="example">
|
|
|
|
<p>The following sample shows how a script element can be used to
|
|
define a function that is then used by other parts of the
|
|
document. It also shows how a <code><a href="#the-script-element">script</a></code> element can be
|
|
used to invoke script while the document is being parsed, in this
|
|
case to initialize the form's output.</p>
|
|
|
|
<pre><script>
|
|
function calculate(form) {
|
|
var price = 52000;
|
|
if (form.elements.brakes.checked)
|
|
price += 1000;
|
|
if (form.elements.radio.checked)
|
|
price += 2500;
|
|
if (form.elements.turbo.checked)
|
|
price += 5000;
|
|
if (form.elements.sticker.checked)
|
|
price += 250;
|
|
form.elements.result.value = price;
|
|
}
|
|
</script>
|
|
<form name="pricecalc" onsubmit="return false" onchange="calculate(this)">
|
|
<fieldset>
|
|
<legend>Work out the price of your car</legend>
|
|
<p>Base cost: £52000.</p>
|
|
<p>Select additional options:</p>
|
|
<ul>
|
|
<li><label><input type=checkbox name=brakes> Ceramic brakes (£1000)</label></li>
|
|
<li><label><input type=checkbox name=radio> Satellite radio (£2500)</label></li>
|
|
<li><label><input type=checkbox name=turbo> Turbo charger (£5000)</label></li>
|
|
<li><label><input type=checkbox name=sticker> "XZ" sticker (£250)</label></li>
|
|
</ul>
|
|
<p>Total: £<output name=result></output></p>
|
|
</fieldset>
|
|
<script>
|
|
calculate(document.forms.pricecalc);
|
|
</script>
|
|
</form></pre>
|
|
|
|
</div><h5 id="scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</h5><div class="impl">
|
|
|
|
<p>A user agent is said to <dfn id="support-the-scripting-language">support the scripting language</dfn>
|
|
if <var><a href="#the-script-block-s-type">the script block's type</a></var> is an <a href="infrastructure.html#ascii-case-insensitive">ASCII
|
|
case-insensitive</a> match for the <a href="infrastructure.html#mime-type">MIME type</a> string
|
|
of a scripting language that the user agent implements.</p>
|
|
|
|
</div><p>The following lists some <a href="infrastructure.html#mime-type">MIME type</a> strings and the
|
|
languages to which they refer:</p><dl><dt>"<code>application/ecmascript</code>"</dt>
|
|
<dt>"<code>application/javascript</code>"</dt>
|
|
<dt>"<code>application/x-ecmascript</code>"</dt>
|
|
<dt>"<code>application/x-javascript</code>"</dt>
|
|
<dt>"<code>text/ecmascript</code>"</dt>
|
|
<dt>"<code>text/javascript</code>"</dt>
|
|
<dt>"<code>text/javascript1.0</code>"</dt>
|
|
<dt>"<code>text/javascript1.1</code>"</dt>
|
|
<dt>"<code>text/javascript1.2</code>"</dt>
|
|
<dt>"<code>text/javascript1.3</code>"</dt>
|
|
<dt>"<code>text/javascript1.4</code>"</dt>
|
|
<dt>"<code>text/javascript1.5</code>"</dt>
|
|
<dt>"<code>text/jscript</code>"</dt>
|
|
<dt>"<code>text/livescript</code>"</dt>
|
|
<dt>"<code>text/x-ecmascript</code>"</dt>
|
|
<dt>"<code>text/x-javascript</code>"</dt>
|
|
<dd>JavaScript. <a href="references.html#refsECMA262">[ECMA262]</a></dd>
|
|
|
|
<dt>"<code>text/javascript;e4x=1</code>"</dt>
|
|
<dd>JavaScript with ECMAScript for XML. <a href="references.html#refsECMA357">[ECMA357]</a></dd>
|
|
|
|
</dl><div class="impl">
|
|
|
|
<p>User agents may support other <a href="infrastructure.html#mime-type" title="MIME type">MIME
|
|
types</a> and other languages.</p>
|
|
|
|
|
|
<p>When examining types to determine if they support the language,
|
|
user agents must not ignore unknown MIME parameters — types
|
|
with unknown parameters must be assumed to be unsupported. The <code title="">charset</code> parameter must be treated as an unknown
|
|
parameter for the purpose of comparing <a href="infrastructure.html#mime-type" title="MIME type">MIME
|
|
types</a> here.</p>
|
|
|
|
</div><h5 id="restrictions-for-contents-of-script-elements"><span class="secno">4.3.1.2 </span><dfn title="script content restrictions">Restrictions for contents of <code>script</code> elements</dfn></h5><p>The <code><a href="infrastructure.html#textcontent">textContent</a></code> of a <code><a href="#the-script-element">script</a></code> element
|
|
must match the <code title="">script</code> production in the
|
|
following ABNF, the character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>script = data1 *( escape [ script-start data3 ] "-->" data1 ) [ escape ]
|
|
escape = "<!--" data2 *( script-start data3 script-end data2 )
|
|
|
|
data1 = <any string that doesn't contain a substring that matches not-data1>
|
|
not-data1 = "<!--"
|
|
|
|
data2 = <any string that doesn't contain a substring that matches not-data2>
|
|
not-data2 = script-start / "-->"
|
|
|
|
data3 = <any string that doesn't contain a substring that matches not-data3>
|
|
not-data3 = script-end / "-->"
|
|
|
|
script-start = lt s c r i p t tag-end
|
|
script-end = lt slash s c r i p t tag-end
|
|
|
|
lt = %x003C ; U+003C LESS-THAN SIGN character (<)
|
|
slash = %x002F ; U+002F SOLIDUS character (/)
|
|
|
|
s = %x0053 ; U+0053 LATIN CAPITAL LETTER S
|
|
s =/ %x0073 ; U+0073 LATIN SMALL LETTER S
|
|
c = %x0043 ; U+0043 LATIN CAPITAL LETTER C
|
|
c =/ %x0063 ; U+0063 LATIN SMALL LETTER C
|
|
r = %x0052 ; U+0052 LATIN CAPITAL LETTER R
|
|
r =/ %x0072 ; U+0072 LATIN SMALL LETTER R
|
|
i = %x0049 ; U+0049 LATIN CAPITAL LETTER I
|
|
i =/ %x0069 ; U+0069 LATIN SMALL LETTER I
|
|
p = %x0050 ; U+0050 LATIN CAPITAL LETTER P
|
|
p =/ %x0070 ; U+0070 LATIN SMALL LETTER P
|
|
t = %x0054 ; U+0054 LATIN CAPITAL LETTER T
|
|
t =/ %x0074 ; U+0074 LATIN SMALL LETTER T
|
|
|
|
tag-end = %x0009 ; U+0009 CHARACTER TABULATION (tab)
|
|
tag-end =/ %x000A ; U+000A LINE FEED (LF)
|
|
tag-end =/ %x000C ; U+000C FORM FEED (FF)
|
|
tag-end =/ %x0020 ; U+0020 SPACE
|
|
tag-end =/ %x002F ; U+002F SOLIDUS (/)
|
|
tag-end =/ %x003E ; U+003E GREATER-THAN SIGN (>)</pre><p>When a <code><a href="#the-script-element">script</a></code> element contains <a href="#inline-documentation-for-external-scripts">script
|
|
documentation</a>, there are further restrictions on the contents
|
|
of the element, as described in the section below.</p><h5 id="inline-documentation-for-external-scripts"><span class="secno">4.3.1.3 </span><dfn title="script documentation">Inline documentation for external scripts</dfn></h5><p>If a <code><a href="#the-script-element">script</a></code> element's <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is specified, then the
|
|
contents of the <code><a href="#the-script-element">script</a></code> element, if any, must be such
|
|
that the value of the <code title="dom-script-text"><a href="#dom-script-text">text</a></code> IDL
|
|
attribute, which is derived from the element's contents, matches the
|
|
<code title="">documentation</code> production in the following
|
|
ABNF, the character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>documentation = *( *( space / tab / comment ) [ line-comment ] newline )
|
|
comment = slash star *( not-star / star not-slash ) 1*star slash
|
|
line-comment = slash slash *not-newline
|
|
|
|
; characters
|
|
tab = %x0009 ; U+0009 CHARACTER TABULATION (tab)
|
|
newline = %x000A ; U+000A LINE FEED (LF)
|
|
space = %x0020 ; U+0020 SPACE
|
|
star = %x002A ; U+002A ASTERISK (*)
|
|
slash = %x002F ; U+002F SOLIDUS (/)
|
|
not-newline = %x0000-0009 / %x000B-10FFFF
|
|
; a Unicode character other than U+000A LINE FEED (LF)
|
|
not-star = %x0000-0029 / %x002B-10FFFF
|
|
; a Unicode character other than U+002A ASTERISK (*)
|
|
not-slash = %x0000-002E / %x0030-10FFFF
|
|
; a Unicode character other than U+002F SOLIDUS (/)</pre><p class="note">This corresponds to putting the contents of the
|
|
element in JavaScript comments.</p><p class="note">This requirement is in addition to the earlier
|
|
restrictions on the syntax of contents of <code><a href="#the-script-element">script</a></code>
|
|
elements.</p><div class="example">
|
|
|
|
<p>This allows authors to include documentation, such as license
|
|
information or API information, inside their documents while still
|
|
referring to external script files. The syntax is constrained so
|
|
that authors don't accidentally include what looks like valid
|
|
script while also providing a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute.</p>
|
|
|
|
<pre><script src="cool-effects.js">
|
|
// create new instances using:
|
|
// var e = new Effect();
|
|
// start the effect using .play, stop using .stop:
|
|
// e.play();
|
|
// e.stop();
|
|
</script></pre>
|
|
|
|
</div><div class="impl">
|
|
|
|
<h5 id="scriptTagXSLT"><span class="secno">4.3.1.4 </span>Interaction of <code><a href="#the-script-element">script</a></code> elements and XSLT</h5>
|
|
|
|
<p><i>This section is non-normative.</i></p>
|
|
|
|
<p>This specification does not define how XSLT interacts with the
|
|
<code><a href="#the-script-element">script</a></code> element (or, indeed, how XSLT processing
|
|
triggers the <a href="the-end.html#stop-parsing">stop parsing</a> steps, how it interacts with
|
|
the <a href="history.html#navigate" title="navigate">navigation</a> algorithm, or how it
|
|
fits in with the <a href="webappapis.html#event-loop">event loop</a>). However, in the absence
|
|
of another specification actually defining this, here are some
|
|
guidelines for implementors, based on existing implementations:</p>
|
|
|
|
<ul><li><p>When an XSLT transformation program is triggered by an <code title=""><?xml-stylesheet?></code> processing instruction and
|
|
the browser implements a direct-to-DOM transformation,
|
|
<code><a href="#the-script-element">script</a></code> elements created by the XSLT processor need to
|
|
be marked <a href="#parser-inserted">"parser-inserted"</a> and run in document order
|
|
(modulo scripts marked <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code>
|
|
or <code title="attr-script-async"><a href="#attr-script-async">async</a></code>), asynchronously
|
|
while the transformation is occurring.</p></li>
|
|
|
|
<li><p>The <code title="dom-XSLTProcessor-transformToDocument">XSLTProcessor.transformToDocument()</code>
|
|
method adds elements to a <code><a href="infrastructure.html#document">Document</a></code> that is not in a
|
|
<a href="browsers.html#browsing-context">browsing context</a>, and, accordingly, any
|
|
<code><a href="#the-script-element">script</a></code> elements they create need to have their
|
|
<a href="#already-started">"already started"</a> flag set in the <a href="#prepare-a-script">prepare a
|
|
script</a> algorithm and never get executed (<a href="webappapis.html#concept-bc-noscript" title="concept-bc-noscript">scripting is disabled</a>). Such
|
|
<code><a href="#the-script-element">script</a></code> elements still need to be marked
|
|
<a href="#parser-inserted">"parser-inserted"</a>, though, such that their <code title="dom-script-async"><a href="#dom-script-async">async</a></code> IDL attribute will return
|
|
false in the absence of an <code title="attr-script-async"><a href="#attr-script-async">async</a></code> content attribute.</p></li>
|
|
|
|
<li><p>The <code title="dom-XSLTProcessor-transformToFragment">XSLTProcessor.transformToFragment()</code>
|
|
method needs to create a fragment that is equivalent to one built
|
|
manually by creating the elements using <code title="dom-document-createElementNS"><a href="infrastructure.html#dom-document-createelementns">document.createElementNS()</a></code>.
|
|
For instance, it needs to create <code><a href="#the-script-element">script</a></code> elements that
|
|
aren't <a href="#parser-inserted">"parser-inserted"</a> and that don't have their
|
|
<a href="#already-started">"already started"</a> flag set, so that they will execute
|
|
when the fragment is inserted into a document.</p></li>
|
|
|
|
</ul><p>The main distinction between the first two cases and the last
|
|
case is that the first two operate on <code><a href="infrastructure.html#document">Document</a></code>s and the
|
|
last operates on a fragment.</p>
|
|
|
|
</div><h4 id="the-noscript-element"><span class="secno">4.3.2 </span>The <dfn><code>noscript</code></dfn> element</h4><dl class="element"><dt>Categories</dt>
|
|
<dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
|
|
<dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
|
|
<dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
|
|
<dt>Contexts in which this element can be used:</dt>
|
|
<dd>In a <code><a href="semantics.html#the-head-element">head</a></code> element of an <a href="dom.html#html-documents" title="HTML documents">HTML document</a>, if there are no ancestor <code><a href="#the-noscript-element">noscript</a></code> elements.</dd>
|
|
<dd>Where <a href="content-models.html#phrasing-content">phrasing content</a> is expected in <a href="dom.html#html-documents">HTML documents</a>, if there are no ancestor <code><a href="#the-noscript-element">noscript</a></code> elements.</dd>
|
|
<dt>Content model:</dt>
|
|
<dd>When <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, in a <code><a href="semantics.html#the-head-element">head</a></code> element: in any order, zero or more <code><a href="semantics.html#the-link-element">link</a></code> elements, zero or more <code><a href="semantics.html#the-style-element">style</a></code> elements, and zero or more <code><a href="semantics.html#the-meta-element">meta</a></code> elements.</dd>
|
|
<dd>When <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, not in a <code><a href="semantics.html#the-head-element">head</a></code> element: <a href="content-models.html#transparent">transparent</a>, but there must be no <code><a href="#the-noscript-element">noscript</a></code> element descendants.</dd>
|
|
<dd>Otherwise: text that conforms to the requirements given in the prose.</dd>
|
|
<dt>Content attributes:</dt>
|
|
<dd><a href="elements.html#global-attributes">Global attributes</a></dd>
|
|
<dt>DOM interface:</dt>
|
|
<dd>Uses <code><a href="elements.html#htmlelement">HTMLElement</a></code>.</dd>
|
|
</dl><p>The <code><a href="#the-noscript-element">noscript</a></code> element <a href="rendering.html#represents">represents</a> nothing
|
|
if <a href="webappapis.html#concept-n-script" title="concept-n-script">scripting is enabled</a>, and
|
|
<a href="rendering.html#represents">represents</a> its children if <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>. It is used
|
|
to present different markup to user agents that support scripting
|
|
and those that don't support scripting, by affecting how the
|
|
document is parsed.</p><p>When used in <a href="dom.html#html-documents">HTML documents</a>, the allowed content
|
|
model is as follows:</p><dl><dt>In a <code><a href="semantics.html#the-head-element">head</a></code> element, if <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
|
|
<code><a href="#the-noscript-element">noscript</a></code> element</dt>
|
|
|
|
<dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only
|
|
<code><a href="semantics.html#the-link-element">link</a></code>, <code><a href="semantics.html#the-style-element">style</a></code>, and <code><a href="semantics.html#the-meta-element">meta</a></code>
|
|
elements.</p></dd>
|
|
|
|
<dt>In a <code><a href="semantics.html#the-head-element">head</a></code> element, if <a href="webappapis.html#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
|
|
<code><a href="#the-noscript-element">noscript</a></code> element</dt>
|
|
|
|
<dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
|
|
except that invoking the <a href="the-end.html#html-fragment-parsing-algorithm">HTML fragment parsing
|
|
algorithm</a> with
|
|
the <code><a href="#the-noscript-element">noscript</a></code> element as the <var title="concept-frag-parse-context"><a href="the-end.html#concept-frag-parse-context">context</a></var> element and the
|
|
text contents as the <var title="">input</var> must result in a
|
|
list of nodes that consists only of <code><a href="semantics.html#the-link-element">link</a></code>,
|
|
<code><a href="semantics.html#the-style-element">style</a></code>, and <code><a href="semantics.html#the-meta-element">meta</a></code> elements that would be
|
|
conforming if they were children of the <code><a href="#the-noscript-element">noscript</a></code>
|
|
element, and no <a href="parsing.html#parse-error" title="parse error">parse
|
|
errors</a>.</p></dd>
|
|
|
|
<dt>Outside of <code><a href="semantics.html#the-head-element">head</a></code> elements, if <a href="webappapis.html#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
|
|
<code><a href="#the-noscript-element">noscript</a></code> element</dt>
|
|
|
|
<dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element's content model is
|
|
<a href="content-models.html#transparent">transparent</a>, with the additional restriction that a
|
|
<code><a href="#the-noscript-element">noscript</a></code> element must not have a <code><a href="#the-noscript-element">noscript</a></code>
|
|
element as an ancestor (that is, <code><a href="#the-noscript-element">noscript</a></code> can't be
|
|
nested).</p></dd>
|
|
|
|
<dt>Outside of <code><a href="semantics.html#the-head-element">head</a></code> elements, if <a href="webappapis.html#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
|
|
<code><a href="#the-noscript-element">noscript</a></code> element</dt>
|
|
|
|
<dd>
|
|
|
|
<p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
|
|
except that the text must be such that running the following
|
|
algorithm results in a conforming document with no
|
|
<code><a href="#the-noscript-element">noscript</a></code> elements and no <code><a href="#the-script-element">script</a></code>
|
|
elements, and such that no step in the algorithm causes an
|
|
<a href="parsing.html#html-parser">HTML parser</a> to flag a <a href="parsing.html#parse-error">parse error</a>:</p>
|
|
|
|
<ol><li>Remove every <code><a href="#the-script-element">script</a></code> element from the
|
|
document.</li>
|
|
|
|
<li>Make a list of every <code><a href="#the-noscript-element">noscript</a></code> element in the
|
|
document. For every <code><a href="#the-noscript-element">noscript</a></code> element in that list,
|
|
perform the following steps:
|
|
|
|
<ol><li>Let the <var title="">parent element</var> be the parent
|
|
element of the <code><a href="#the-noscript-element">noscript</a></code> element.</li>
|
|
|
|
<li>Take all the children of the <var title="">parent element</var>
|
|
that come before the <code><a href="#the-noscript-element">noscript</a></code> element, and call these
|
|
elements <var title="">the before children</var>.</li>
|
|
|
|
<li>Take all the children of the <var title="">parent element</var>
|
|
that come <em>after</em> the <code><a href="#the-noscript-element">noscript</a></code> element, and
|
|
call these elements <var title="">the after children</var>.</li>
|
|
|
|
<li>Let <var title="">s</var> be the concatenation of all the
|
|
<a href="infrastructure.html#text-node">text node</a> children of the <code><a href="#the-noscript-element">noscript</a></code>
|
|
element.</li>
|
|
|
|
<li>Set the <code title="dom-innerHTML"><a href="apis-in-html-documents.html#dom-innerhtml">innerHTML</a></code>
|
|
attribute of the <var title="">parent element</var> to the value
|
|
of <var title="">s</var>. (This, as a side-effect, causes the
|
|
<code><a href="#the-noscript-element">noscript</a></code> element to be removed from the
|
|
document.)</li>
|
|
|
|
<li>Insert <var title="">the before children</var> at the start of
|
|
the <var title="">parent element</var>, preserving their original
|
|
relative order.</li>
|
|
|
|
<li>Insert <var title="">the after children</var> at the end of the
|
|
<var title="">parent element</var>, preserving their original
|
|
relative order.</li>
|
|
|
|
</ol></li>
|
|
|
|
</ol></dd>
|
|
|
|
</dl><p class="note">All these contortions are required because, for
|
|
historical reasons, the <code><a href="#the-noscript-element">noscript</a></code> element is handled
|
|
differently by the <a href="parsing.html#html-parser">HTML parser</a> based on whether <a href="parsing.html#scripting-flag" title="scripting flag">scripting was enabled or not</a> when the
|
|
parser was invoked.</p><p>The <code><a href="#the-noscript-element">noscript</a></code> element must not be used in <a href="dom.html#xml-documents">XML
|
|
documents</a>.</p><p class="note"><strong>The <code><a href="#the-noscript-element">noscript</a></code> element is only
|
|
effective in <a href="syntax.html#syntax">the HTML syntax</a>, it has no effect in
|
|
<a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML syntax</a>.</strong></p><div class="impl">
|
|
|
|
<p>The <code><a href="#the-noscript-element">noscript</a></code> element has no other requirements. In
|
|
particular, children of the <code><a href="#the-noscript-element">noscript</a></code> element are not
|
|
exempt from <a href="association-of-controls-and-forms.html#form-submission">form submission</a>, scripting, and so forth,
|
|
even when <a href="webappapis.html#concept-n-script" title="concept-n-script">scripting is enabled</a>
|
|
for the element.</p>
|
|
|
|
</div><div class="example">
|
|
|
|
<p>In the following example, a <code><a href="#the-noscript-element">noscript</a></code> element is
|
|
used to provide fallback for a script.</p>
|
|
|
|
<pre><form action="calcSquare.php">
|
|
<p>
|
|
<label for=x>Number</label>:
|
|
<input id="x" name="x" type="number">
|
|
</p>
|
|
<script>
|
|
var x = document.getElementById('x');
|
|
var output = document.createElement('p');
|
|
output.textContent = 'Type a number; it will be squared right then!';
|
|
x.form.appendChild(output);
|
|
x.form.onsubmit = function () { return false; }
|
|
x.oninput = function () {
|
|
var v = x.valueAsNumber;
|
|
output.textContent = v + ' squared is ' + v * v;
|
|
};
|
|
</script>
|
|
<noscript>
|
|
<input type=submit value="Calculate Square">
|
|
</noscript>
|
|
</form></pre>
|
|
|
|
<p>When script is disabled, a button appears to do the calculation
|
|
on the server side. When script is enabled, the value is computed
|
|
on-the-fly instead.</p>
|
|
|
|
<p>The <code><a href="#the-noscript-element">noscript</a></code> element is a blunt
|
|
instrument. Sometimes, scripts might be enabled, but for some
|
|
reason the page's script might fail. For this reason, it's
|
|
generally better to avoid using <code><a href="#the-noscript-element">noscript</a></code>, and to
|
|
instead design the script to change the page from being a
|
|
scriptless page to a scripted page on the fly, as in the next
|
|
example:</p>
|
|
|
|
<pre><form action="calcSquare.php">
|
|
<p>
|
|
<label for=x>Number</label>:
|
|
<input id="x" name="x" type="number">
|
|
</p>
|
|
<strong><input id="submit" type=submit value="Calculate Square"></strong>
|
|
<script>
|
|
var x = document.getElementById('x');
|
|
var output = document.createElement('p');
|
|
output.textContent = 'Type a number; it will be squared right then!';
|
|
x.form.appendChild(output);
|
|
x.form.onsubmit = function () { return false; }
|
|
x.oninput = function () {
|
|
var v = x.valueAsNumber;
|
|
output.textContent = v + ' squared is ' + v * v;
|
|
};
|
|
<strong> var submit = document.getElementById('submit');
|
|
submit.parentNode.removeChild(submit);</strong>
|
|
</script>
|
|
</form></pre>
|
|
|
|
<p>The above technique is also useful in XHTML, since
|
|
<code><a href="#the-noscript-element">noscript</a></code> is not supported in <a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML
|
|
syntax</a>.</p>
|
|
|
|
</div></body></html>
|