Annotation of html5/spec-author-view/scripting-1.html, revision 1.34
1.9 mike 1: <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
2: <!DOCTYPE html>
3: <!-- when publishing, change bits marked ZZZ --><html lang="en-US-x-Hixie" class="split chapter"><head><title>4.3 Scripting — HTML5 (Author Edition)</title><script src="link-fixup.js"></script><link href="whatwg.css" rel="stylesheet"><style type="text/css">
4: pre { margin-left: 2em; white-space: pre-wrap; }
5: h2 { margin: 3em 0 1em 0; }
6: h3 { margin: 2.5em 0 1em 0; }
7: h4 { margin: 2.5em 0 0.75em 0; }
8: h5, h6 { margin: 2.5em 0 1em; }
9: h1 + h2, h1 + h2 + h2 { margin: 0.75em 0 0.75em; }
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11: p { margin: 1em 0; }
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13: dl, dd { margin-top: 0; margin-bottom: 0; }
14: dt { margin-top: 0.75em; margin-bottom: 0.25em; clear: left; }
15: dt + dt { margin-top: 0; }
16: dd dt { margin-top: 0.25em; margin-bottom: 0; }
17: dd p { margin-top: 0; }
18: dd dl + p { margin-top: 1em; }
19: dd table + p { margin-top: 1em; }
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22: dt dfn { font-style: italic; }
23: pre, code { font-size: inherit; font-family: monospace; font-variant: normal; }
24: pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
25: pre em { font-weight: bolder; font-style: normal; }
26: @media screen { code { color: orangered; } code :link, code :visited { color: inherit; } }
27: var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
28: table { border-collapse: collapse; border-style: hidden hidden none hidden; }
1.32 mike 29: table thead, table tbody { border-bottom: solid; }
1.9 mike 30: table tbody th:first-child { border-left: solid; }
31: table tbody th { text-align: left; }
32: table td, table th { border-left: solid; border-right: solid; border-bottom: solid thin; vertical-align: top; padding: 0.2em; }
33: blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }
34:
35: .bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
36: .matrix, .matrix td { border: none; text-align: right; }
37: .matrix { margin-left: 2em; }
38: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
39: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
40: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
41:
42: .toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
43: img.extra { float: right; }
44: pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; }
45: pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
46: pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
47: pre.css:first-line { color: #AAAA50; }
1.17 mike 48: dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #DDFFDD; }
1.9 mike 49: hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
50: dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
51: dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
52: dl.domintro dd p { margin: 0.5em 0; }
53: dl.switch { padding-left: 2em; }
54: dl.switch > dt { text-indent: -1.5em; }
55: dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
56: dl.triple { padding: 0 0 0 1em; }
57: dl.triple dt, dl.triple dd { margin: 0; display: inline }
58: dl.triple dt:after { content: ':'; }
59: dl.triple dd:after { content: '\A'; white-space: pre; }
60: .diff-old { text-decoration: line-through; color: silver; background: transparent; }
61: .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
62: a .diff-new { border-bottom: 1px blue solid; }
63:
64: h2 { page-break-before: always; }
65: h1, h2, h3, h4, h5, h6 { page-break-after: avoid; }
66: h1 + h2, hr + h2.no-toc { page-break-before: auto; }
67:
68: p > span:not([title=""]):not([class="XXX"]):not([class="impl"]), li > span:not([title=""]):not([class="XXX"]):not([class="impl"]) { border-bottom: solid #9999CC; }
69:
70: div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
71: div.head p { margin: 0; }
72: div.head h1 { margin: 0; }
73: div.head .logo { float: right; margin: 0 1em; }
74: div.head .logo img { border: none } /* remove border from top image */
75: div.head dl { margin: 1em 0; }
76: div.head p.copyright, div.head p.alt { font-size: x-small; font-style: oblique; margin: 0; }
77:
78: body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
79: body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
80: body > .toc > li > * { margin-bottom: 0.5em; }
81: body > .toc > li > * > li > * { margin-bottom: 0.25em; }
82: .toc, .toc li { list-style: none; }
83:
84: .brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
85: .brief li { margin: 0; padding: 0; }
86: .brief li p { margin: 0; padding: 0; }
87:
88: .category-list { margin-top: -0.75em; margin-bottom: 1em; line-height: 1.5; }
89: .category-list::before { content: '\21D2\A0'; font-size: 1.2em; font-weight: 900; }
90: .category-list li { display: inline; }
91: .category-list li:not(:last-child)::after { content: ', '; }
92: .category-list li > span, .category-list li > a { text-transform: lowercase; }
93: .category-list li * { text-transform: none; } /* don't affect <code> nested in <a> */
94:
95: .XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
96: .XXX > :first-child { margin-top: 0; }
97: p .XXX { line-height: 3em; }
98: .annotation { border: solid thin black; background: #0C479D; color: white; position: relative; margin: 8px 0 20px 0; }
99: .annotation:before { position: absolute; left: 0; top: 0; width: 100%; height: 100%; margin: 6px -6px -6px 6px; background: #333333; z-index: -1; content: ''; }
100: .annotation :link, .annotation :visited { color: inherit; }
101: .annotation :link:hover, .annotation :visited:hover { background: transparent; }
102: .annotation span { border: none ! important; }
103: .note { color: green; background: transparent; font-family: sans-serif; }
104: .warning { color: red; background: transparent; }
105: .note, .warning { font-weight: bolder; font-style: italic; }
106: p.note, div.note { padding: 0.5em 2em; }
107: span.note { padding: 0 2em; }
108: .note p:first-child, .warning p:first-child { margin-top: 0; }
109: .note p:last-child, .warning p:last-child { margin-bottom: 0; }
110: .warning:before { font-style: normal; }
111: p.note:before { content: 'Note: '; }
112: p.warning:before { content: '\26A0 Warning! '; }
113:
114: .bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
115: .bookkeeping { font-size: 0.8em; margin: 2em 0; }
116: .bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }
117:
118: h4 { position: relative; z-index: 3; }
119: h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
120: .element {
121: background: #EEEEFF;
122: color: black;
123: margin: 0 0 1em 0.15em;
124: padding: 0 1em 0.25em 0.75em;
125: border-left: solid #9999FF 0.25em;
126: position: relative;
127: z-index: 1;
128: }
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130: position: absolute;
131: z-index: 2;
132: top: 0;
133: left: -1.15em;
134: height: 2em;
135: width: 0.9em;
136: background: #EEEEFF;
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139: border-color: #9999FF;
140: border-width: 0.25em;
141: }
142:
143: .example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
144: td > .example:only-child { margin: 0 0 0 0.1em; }
145:
146: ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
147: ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
148: ul.domTree li li { list-style: none; }
149: 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; }
150: 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; }
151: ul.domTree span { font-style: italic; font-family: serif; }
152: ul.domTree .t1 code { color: purple; font-weight: bold; }
153: ul.domTree .t2 { font-style: normal; font-family: monospace; }
154: ul.domTree .t2 .name { color: black; font-weight: bold; }
155: ul.domTree .t2 .value { color: blue; font-weight: normal; }
156: ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
157: ul.domTree .t7 code, .domTree .t8 code { color: green; }
158: ul.domTree .t10 code { color: teal; }
159:
1.13 mike 160: body.dfnEnabled dfn { cursor: pointer; }
161: .dfnPanel {
162: display: inline;
163: position: absolute;
164: z-index: 10;
165: height: auto;
166: width: auto;
167: padding: 0.5em 0.75em;
168: font: small sans-serif, Droid Sans Fallback;
169: background: #DDDDDD;
170: color: black;
171: border: outset 0.2em;
172: }
173: .dfnPanel * { margin: 0; padding: 0; font: inherit; text-indent: 0; }
174: .dfnPanel :link, .dfnPanel :visited { color: black; }
175: .dfnPanel p { font-weight: bolder; }
176: .dfnPanel * + p { margin-top: 0.25em; }
177: .dfnPanel li { list-style-position: inside; }
178:
1.9 mike 179: #configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
180: #configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
181: #configUI p label { display: block; }
182: #configUI #updateUI, #configUI .loginUI { text-align: center; }
183: #configUI input[type=button] { display: block; margin: auto; }
184: </style><style type="text/css">
185:
186: .applies thead th > * { display: block; }
187: .applies thead code { display: block; }
188: .applies tbody th { whitespace: nowrap; }
189: .applies td { text-align: center; }
190: .applies .yes { background: yellow; }
191:
192: .matrix, .matrix td { border: none; text-align: right; }
193: .matrix { margin-left: 2em; }
194:
195: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
196: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
197: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
198:
199: #table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
200: #table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
201: #table-example-1 caption { padding-bottom: 0.5em; }
202: #table-example-1 thead, #table-example-1 tbody { border: none; }
203: #table-example-1 th, #table-example-1 td { border: solid thin; }
204: #table-example-1 th { font-weight: normal; }
205: #table-example-1 td { border-style: none solid; vertical-align: top; }
206: #table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
207: #table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
208: #table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
209: #table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
210: #table-example-1 tbody td:first-child::after { content: leader(". "); }
211: #table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
212: #table-example-1 tbody td:first-child + td { width: 10em; }
213: #table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
214: #table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
215:
216: .apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
217: .apple-table-examples * { font-family: "Times", serif; }
218: .apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
219: .apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
220: .apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
221: .apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
222: .apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
223: .apple-table-examples td { text-align: right; vertical-align: top; }
224: .apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
1.11 mike 225: .apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
226: .apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
227: .apple-table-examples sup { line-height: 0; }
228:
1.12 mike 229: .details-example img { vertical-align: top; }
230:
1.22 mike 231: #named-character-references-table {
232: font-size: 0.6em;
233: column-width: 28em;
234: column-gap: 1em;
235: -moz-column-width: 28em;
236: -moz-column-gap: 1em;
237: -webkit-column-width: 28em;
238: -webkit-column-gap: 1em;
239: }
240: #named-character-references-table > table > tbody > tr > td:last-child { text-align: center; }
241: #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; }
242:
1.33 mike 243: .glyph.control { color: red; }
244:
1.18 mike 245: </style><style type="text/css">
1.21 mike 246: .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; }
247: </style><link href="data:text/css," id="complete" rel="stylesheet" title="Complete specification"><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 requirements"><script type="text/javascript">
1.11 mike 248: function getCookie(name) {
249: var params = location.search.substr(1).split("&");
250: for (var index = 0; index < params.length; index++) {
251: if (params[index] == name)
252: return "1";
253: var data = params[index].split("=");
254: if (data[0] == name)
255: return unescape(data[1]);
256: }
257: var cookies = document.cookie.split("; ");
258: for (var index = 0; index < cookies.length; index++) {
259: var data = cookies[index].split("=");
260: if (data[0] == name)
261: return unescape(data[1]);
262: }
263: return null;
264: }
265: function load(script) {
266: var e = document.createElement('script');
267: e.setAttribute('src', 'http://www.whatwg.org/specs/web-apps/current-work/' + script + '?' + encodeURIComponent(location) + '&' + encodeURIComponent(document.referrer));
268: document.body.appendChild(e);
269: }
270: function init() {
271: if (location.search == '?slow-browser')
272: return;
273: var configUI = document.createElement('div');
274: configUI.id = 'configUI';
275: document.body.appendChild(configUI);
276: // load('reviewer.js'); // would need cross-site XHR
277: if (document.getElementById('head'))
278: load('toc.js');
279:
280: // load('updater.js'); // would need cross-site XHR
1.12 mike 281: load('dfn.js'); // doesn't support split-out specs, but, oh well.
1.11 mike 282: // load('status.js'); // would need cross-site XHR
283: if (getCookie('profile') == '1')
284: document.getElementsByTagName('h2')[0].textContent += '; load: ' + (new Date() - loadTimer) + 'ms';
285: fixBrokenLink();
286: }
1.30 mike 287: </script><link href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet" type="text/css"><link href="semantics.html" title="4 The elements of HTML" rel="prev">
1.11 mike 288: <link href="Overview.html#contents" title="Table of contents" rel="index">
289: <link href="sections.html" title="4.4 Sections" rel="next">
290: </head><body onload="fixBrokenLink(); init()"><div class="head" id="head">
291: <p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
1.34 ! mike 292:
1.11 mike 293: <h1>HTML5 (Author Edition)</h1>
294: </div><div>
295: <a href="semantics.html">← 4 The elements of HTML</a> –
296: <a href="Overview.html#contents">Table of contents</a> –
297: <a href="sections.html">4.4 Sections →</a>
298: <ol class="toc"><li><ol><li><a href="scripting-1.html#scripting-1"><span class="secno">4.3 </span>Scripting</a>
299: <ol><li><a href="scripting-1.html#script"><span class="secno">4.3.1 </span>The <code>script</code> element</a>
300: <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></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>
301:
1.28 mike 302: <h3 id="scripting-1"><span class="secno">4.3 </span>Scripting</h3><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>Scripts allow authors to add interactivity to their documents.</p><p>Authors are encouraged to use declarative alternatives to
1.11 mike 303: scripting where possible, as declarative mechanisms are often more
304: maintainable, and many users disable scripting.</p><div class="example">
305: <p>For example, instead of using script to show or hide a section
306: to show more details, the <code><a href="interactive-elements.html#the-details-element">details</a></code> element could be
307: used.</p>
308: </div><p>Authors are also encouraged to make their applications degrade
309: gracefully in the absence of scripting support.</p><div class="example">
310: <p>For example, if an author provides a link in a table header to
311: dynamically resort the table, the link could also be made to
312: function without scripts by requesting the sorted table from the
313: server.</p>
1.28 mike 314: </div><h4 id="script"><span class="secno">4.3.1 </span>The <dfn><code>script</code></dfn> element</h4><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><dl class="element"><dt>Categories</dt>
1.11 mike 315: <dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
316: <dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
317: <dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
318: <dt>Contexts in which this element may be used:</dt>
319: <dd>Where <a href="content-models.html#metadata-content">metadata content</a> is expected.</dd>
320: <dd>Where <a href="content-models.html#phrasing-content">phrasing content</a> is expected.</dd>
321: <dt>Content model:</dt>
322: <dd>If there is no <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
323: attribute, depends on the value of the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, but must match
324: <a href="#restrictions-for-contents-of-script-elements">script content restrictions</a>.</dd>
325: <dd>If there <em>is</em> a <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
326: attribute, the element must be either empty or contain only
327: <a href="#inline-documentation-for-external-scripts">script documentation</a> that also matches <a href="#restrictions-for-contents-of-script-elements">script
328: content restrictions</a>.</dd>
329: <dt>Content attributes:</dt>
330: <dd><a href="elements.html#global-attributes">Global attributes</a></dd>
331: <dd><code title="attr-script-src"><a href="#attr-script-src">src</a></code></dd>
332: <dd><code title="attr-script-async"><a href="#attr-script-async">async</a></code></dd>
333: <dd><code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code></dd>
334: <dd><code title="attr-script-type"><a href="#attr-script-type">type</a></code></dd>
335: <dd><code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code></dd>
336: <dt>DOM interface:</dt>
337: <dd>
338: <pre class="idl">interface <dfn id="htmlscriptelement">HTMLScriptElement</dfn> : <a href="elements.html#htmlelement">HTMLElement</a> {
339: attribute DOMString <a href="#dom-script-src" title="dom-script-src">src</a>;
340: attribute boolean <a href="#dom-script-async" title="dom-script-async">async</a>;
341: attribute boolean <a href="#dom-script-defer" title="dom-script-defer">defer</a>;
342: attribute DOMString <a href="#dom-script-type" title="dom-script-type">type</a>;
343: attribute DOMString <a href="#dom-script-charset" title="dom-script-charset">charset</a>;
344: attribute DOMString <a href="#dom-script-text" title="dom-script-text">text</a>;
345: };</pre>
346: </dd>
347: </dl><p>The <code><a href="#script">script</a></code> element allows authors to include dynamic
348: script and data blocks in their documents. The element does not
349: <a href="#represents" title="represents">represent</a> content for the user.</p><p>When used to include dynamic scripts, the scripts may either be
350: embedded inline or may be imported from an external file using the
351: <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute. If the language
352: is not that described by "<code title="">text/javascript</code>",
353: then the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute must
1.22 mike 354: be present, as described below.</p><p>When used to include data blocks (as opposed to scripts), the
355: data must be embedded inline, the format of the data must be given
356: using the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, and
357: the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute must not be
1.11 mike 358: specified.</p><p>The <dfn id="attr-script-type" title="attr-script-type"><code>type</code></dfn>
359: attribute gives the language of the script or format of the data. If
360: the attribute is present, its value must be a <a href="infrastructure.html#valid-mime-type">valid MIME
1.12 mike 361: type</a>. The <code title="">charset</code> parameter must not be
1.14 mike 362: specified. The default, which is used if the attribute is absent,
363: is "<code title="">text/javascript</code>".</p><p>The <dfn id="attr-script-src" title="attr-script-src"><code>src</code></dfn>
1.11 mike 364: attribute, if specified, gives the address of the external script
1.31 mike 365: resource to use. The value of the attribute must be a <a href="urls.html#valid-non-empty-url-potentially-surrounded-by-spaces">valid
366: non-empty URL potentially surrounded by spaces</a> identifying a
367: 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
368: present, or of the type "<code title="">text/javascript</code>", if
369: the attribute is absent. A resource is a script resource of a given
370: type if that type identifies a scripting language and the resource
371: 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>
1.11 mike 372: attribute gives the character encoding of the external script
373: 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
374: attribute is set, its value must be a valid character encoding name,
375: must be an <a href="infrastructure.html#ascii-case-insensitive">ASCII case-insensitive</a> match for the
376: <a href="infrastructure.html#preferred-mime-name">preferred MIME name</a> for that encoding, and must match
377: the encoding given in the <code title="">charset</code> parameter of
378: the <a href="#content-type" title="Content-Type">Content-Type metadata</a> of the
1.26 mike 379: 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
1.11 mike 380: <dfn id="attr-script-defer" title="attr-script-defer"><code>defer</code></dfn> attributes
381: are <a href="common-microsyntaxes.html#boolean-attribute" title="boolean attribute">boolean attributes</a> that
1.29 mike 382: 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
383: specified if the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute
384: is not present.</p><p>There are three possible modes that can be selected using these
1.11 mike 385: attributes. If the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
386: attribute is present, then the script will be executed
387: 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
388: the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute is
389: present, then the script is executed when the page has finished
390: parsing. If neither attribute is present, then the script is
391: fetched and executed immediately, before the user agent continues
1.20 mike 392: parsing the page.</p><p class="note">The exact processing details for these attributes
393: are, for mostly historical reasons, somewhat non-trivial, involving
394: a number of aspects of HTML. The implementation requirements are
395: therefore by necessity scattered throughout the specification. The
396: algorithms below (in this section) describe the core of this
397: processing, but these algorithms reference and are referenced by the
398: parsing rules for <code><a href="#script">script</a></code> <a href="#scriptTag">start</a>
399: and <a href="#scriptEndTag">end</a> tags in HTML, <a href="#scriptForeignEndTag">in foreign content</a>, and <a href="#scriptTagXML">in XML</a>, the rules for the <code title="dom-document-write"><a href="#dom-document-write">document.write()</a></code> method, the
400: 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
1.11 mike 401: specified even if the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
402: attribute is specified, to cause legacy Web browsers that only
403: 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
1.29 mike 404: 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
1.12 mike 405: direct effect; these attribute are only used at specific times
406: described below.</p><!-- by implication, changes to the base URL
407: also have no effect --><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>
1.11 mike 408:
409: <dd>
410:
411: <p>Returns the contents of the element, ignoring child nodes that
412: aren't <a href="infrastructure.html#text-node" title="text node">text nodes</a>.</p>
413:
414: <p>Can be set, to replace the element's children with the given
415: value.</p>
416:
417: </dd>
418:
419: </dl><p class="note">When inserted using the <code title="dom-document-write"><a href="#dom-document-write">document.write()</a></code> method,
420: <code><a href="#script">script</a></code> elements execute (typically synchronously), but
421: 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
422: execute at all.</p><div class="example">
423:
424: <p>In this example, two <code><a href="#script">script</a></code> elements are used. One
425: embeds an external script, and the other includes some data.</p>
426:
427: <pre><script src="game-engine.js"></script>
428: <script type="text/x-game-map">
429: ........U.........e
430: o............A....e
431: .....A.....AAA....e
432: .A..AAA...AAAAA...e
433: </script></pre>
434:
435: <p>The data in this case might be used by the script to generate
436: the map of a video game. The data doesn't have to be used that way,
437: though; maybe the map data is actually embedded in other parts of
438: the page's markup, and the data block here is just used by the
439: site's search engine to help users who are looking for particular
440: features in their game maps.</p>
441:
442: </div><div class="example">
443:
444: <p>The following sample shows how a script element can be used to
445: define a function that is then used by other parts of the
446: document. It also shows how a <code><a href="#script">script</a></code> element can be
447: used to invoke script while the document is being parsed, in this
448: case to initialize the form's output.</p>
449:
450: <pre><script>
451: function calculate(form) {
452: var price = 52000;
453: if (form.elements.brakes.checked)
454: price += 1000;
455: if (form.elements.radio.checked)
456: price += 2500;
457: if (form.elements.turbo.checked)
458: price += 5000;
459: if (form.elements.sticker.checked)
460: price += 250;
461: form.elements.result.value = price;
462: }
463: </script>
464: <form name="pricecalc" onsubmit="return false">
465: <fieldset>
466: <legend>Work out the price of your car</legend>
467: <p>Base cost: £52000.</p>
468: <p>Select additional options:</p>
469: <ul>
470: <li><label><input type=checkbox name=brakes> Ceramic brakes (£1000)</label></li>
471: <li><label><input type=checkbox name=radio> Satellite radio (£2500)</label></li>
472: <li><label><input type=checkbox name=turbo> Turbo charger (£5000)</label></li>
473: <li><label><input type=checkbox name=sticker> "XZ" sticker (£250)</label></li>
474: </ul>
475: <p>Total: £<output name=result onformchange="calculate(form)"></output></p>
476: </fieldset>
477: <script>
478: document.forms.pricecalc.dispatchFormChange();
479: </script>
480: </form></pre>
481:
1.28 mike 482: </div><h5 id="scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</h5><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>The following lists some <a href="infrastructure.html#mime-type">MIME type</a> strings and the
1.11 mike 483: languages to which they refer:</p><dl><dt>"<code>application/ecmascript</code>"</dt>
484: <dt>"<code>application/javascript</code>"</dt>
485: <dt>"<code>application/x-ecmascript</code>"</dt>
486: <dt>"<code>application/x-javascript</code>"</dt>
487: <dt>"<code>text/ecmascript</code>"</dt>
488: <dt>"<code>text/javascript</code>"</dt>
489: <dt>"<code>text/javascript1.0</code>"</dt>
490: <dt>"<code>text/javascript1.1</code>"</dt>
491: <dt>"<code>text/javascript1.2</code>"</dt>
492: <dt>"<code>text/javascript1.3</code>"</dt>
493: <dt>"<code>text/javascript1.4</code>"</dt>
494: <dt>"<code>text/javascript1.5</code>"</dt>
495: <dt>"<code>text/jscript</code>"</dt>
496: <dt>"<code>text/livescript</code>"</dt>
497: <dt>"<code>text/x-ecmascript</code>"</dt>
498: <dt>"<code>text/x-javascript</code>"</dt>
1.26 mike 499: <dd>JavaScript. <a href="references.html#refsECMA262">[ECMA262]</a></dd>
1.11 mike 500:
501: <dt>"<code>text/javascript;e4x=1</code>"</dt>
1.26 mike 502: <dd>JavaScript with ECMAScript for XML. <a href="references.html#refsECMA357">[ECMA357]</a></dd>
1.11 mike 503:
1.28 mike 504: </dl><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 class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>The <code><a href="#textcontent">textContent</a></code> of a <code><a href="#script">script</a></code> element must match the
1.11 mike 505: <code title="">script</code> production in the following ABNF, the
1.26 mike 506: character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>script = data1 *( escape [ script-start data3 ] "-->" data1 ) [ escape ]
1.11 mike 507: escape = "<!--" data2 *( script-start data3 script-end data2 )
508:
509: data1 = <any string that doesn't contain a substring that matches not-data1>
510: not-data1 = <!-- script-end / -->"<!--" <!-- the script-end is redundant here since it would close the element -->
511:
512: data2 = <any string that doesn't contain a substring that matches not-data2>
513: not-data2 = <!-- script-end / -->script-start / "-->" <!-- the script-end is redundant here since it would close the element -->
514:
515: data3 = <any string that doesn't contain a substring that matches not-data3>
516: not-data3 = script-end / "-->"
517:
518: script-start = lt s c r i p t tag-end
519: script-end = lt slash s c r i p t tag-end
520:
521: lt = %x003C ; U+003C LESS-THAN SIGN character (<)
522: slash = %x002F ; U+002F SOLIDUS character (/)
523:
524: s = %x0053 ; U+0053 LATIN CAPITAL LETTER S
525: s =/ %x0073 ; U+0073 LATIN SMALL LETTER S
526: c = %x0043 ; U+0043 LATIN CAPITAL LETTER C
527: c =/ %x0063 ; U+0063 LATIN SMALL LETTER C
528: r = %x0052 ; U+0052 LATIN CAPITAL LETTER R
529: r =/ %x0072 ; U+0072 LATIN SMALL LETTER R
530: i = %x0049 ; U+0049 LATIN CAPITAL LETTER I
531: i =/ %x0069 ; U+0069 LATIN SMALL LETTER I
532: p = %x0050 ; U+0050 LATIN CAPITAL LETTER P
533: p =/ %x0070 ; U+0070 LATIN SMALL LETTER P
534: t = %x0054 ; U+0054 LATIN CAPITAL LETTER T
535: t =/ %x0074 ; U+0074 LATIN SMALL LETTER T
536:
537: tag-end = %x0009 ; U+0009 CHARACTER TABULATION
538: tag-end =/ %x000A ; U+000A LINE FEED (LF)
539: tag-end =/ %x000C ; U+000C FORM FEED (FF)
540: tag-end =/ %x0020 ; U+0020 SPACE
541: tag-end =/ %x002F ; U+002F SOLIDUS (/)
542: tag-end =/ %x003E ; U+003E GREATER-THAN SIGN (>)</pre><p>When a <code><a href="#script">script</a></code> element contains <a href="#inline-documentation-for-external-scripts">script
543: documentation</a>, there are further restrictions on the contents
1.28 mike 544: 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 class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>If a <code><a href="#script">script</a></code> element's <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is specified, then the
1.11 mike 545: contents of the <code><a href="#script">script</a></code> element, if any, must be such
546: that the value of the <code title="dom-script-text"><a href="#dom-script-text">text</a></code> IDL
547: attribute, which is derived from the element's contents, matches the
548: <code title="">documentation</code> production in the following
1.26 mike 549: ABNF, the character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>documentation = *( *( space / tab / comment ) [ line-comment ] newline )
1.11 mike 550: comment = slash star *( not-star / star not-slash ) 1*star slash
551: line-comment = slash slash *not-newline
552:
553: ; characters
554: tab = %x0009 ; U+0009 TAB
555: newline = %x000A ; U+000A LINE FEED (LF)
556: space = %x0020 ; U+0020 SPACE
557: star = %x002A ; U+002A ASTERISK (*)
558: slash = %x002F ; U+002F SOLIDUS (/)
559: not-newline = %x0000-0009 / %x000B-10FFFF
560: ; a Unicode character other than U+000A LINE FEED (LF)
561: not-star = %x0000-0029 / %x002B-10FFFF
562: ; a Unicode character other than U+002A ASTERISK (*)
563: not-slash = %x0000-002E / %x0030-10FFFF
564: ; a Unicode character other than U+002F SOLIDUS (/)</pre><p class="note">This corresponds to putting the contents of the
565: element in JavaScript comments.</p><p class="note">This requirement is in addition to the earlier
566: restrictions on the syntax of contents of <code><a href="#script">script</a></code>
567: elements.</p><div class="example">
568:
569: <p>This allows authors to include documentation, such as license
570: information or API information, inside their documents while still
571: referring to external script files. The syntax is constrained so
572: that authors don't accidentally include what looks like valid
573: script while also providing a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute.</p>
574:
575: <pre><script src="cool-effects.js">
576: // create new instances using:
577: // var e = new Effect();
578: // start the effect using .play, stop using .stop:
579: // e.play();
580: // e.stop();
581: </script></pre>
582:
1.28 mike 583: </div><h4 id="the-noscript-element"><span class="secno">4.3.2 </span>The <dfn><code>noscript</code></dfn> element</h4><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><dl class="element"><dt>Categories</dt>
1.11 mike 584: <dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
585: <dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
586: <dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
587: <dt>Contexts in which this element may be used:</dt>
588: <dd>In a <code><a href="semantics.html#the-head-element-0">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>
589: <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>
590: <dt>Content model:</dt>
591: <dd>When <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, in a <code><a href="semantics.html#the-head-element-0">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#meta">meta</a></code> elements.</dd>
592: <dd>When <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, not in a <code><a href="semantics.html#the-head-element-0">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>
593: <dd>Otherwise: text that conforms to the requirements given in the prose.</dd>
594: <dt>Content attributes:</dt>
595: <dd><a href="elements.html#global-attributes">Global attributes</a></dd>
596: <dt>DOM interface:</dt>
597: <dd>Uses <code><a href="elements.html#htmlelement">HTMLElement</a></code>.</dd>
598: </dl><p>The <code><a href="#the-noscript-element">noscript</a></code> element <a href="#represents">represents</a> nothing
599: if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a>, and
600: <a href="#represents">represents</a> its children if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>. It is used
601: to present different markup to user agents that support scripting
602: and those that don't support scripting, by affecting how the
603: document is parsed.</p><p>When used in <a href="dom.html#html-documents">HTML documents</a>, the allowed content
604: model is as follows:</p><dl><dt>In a <code><a href="semantics.html#the-head-element-0">head</a></code> element, if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
605: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
606:
607: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only
608: <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#meta">meta</a></code>
609: elements.</p></dd>
610:
611: <dt>In a <code><a href="semantics.html#the-head-element-0">head</a></code> element, if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
612: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
613:
614: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
615: except that invoking the <a href="#html-fragment-parsing-algorithm">HTML fragment parsing
1.12 mike 616: algorithm</a> <!-- (which disables <script type="text/javascript"> execution) --> with
1.11 mike 617: the <code><a href="#the-noscript-element">noscript</a></code> element as the <var title="">context</var> element and the text contents as the <var title="">input</var> must result in a list of nodes that consists
618: 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
619: <code><a href="semantics.html#meta">meta</a></code> elements that would be conforming if they were
620: children of the <code><a href="#the-noscript-element">noscript</a></code> element, and no <a href="#parse-error" title="parse error">parse errors</a>.</p></dd>
621:
622: <dt>Outside of <code><a href="semantics.html#the-head-element-0">head</a></code> elements, if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
623: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
624:
625: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element's content model is
626: <a href="content-models.html#transparent">transparent</a>, with the additional restriction that a
627: <code><a href="#the-noscript-element">noscript</a></code> element must not have a <code><a href="#the-noscript-element">noscript</a></code>
628: element as an ancestor (that is, <code><a href="#the-noscript-element">noscript</a></code> can't be
629: nested).</p></dd>
630:
631: <dt>Outside of <code><a href="semantics.html#the-head-element-0">head</a></code> elements, if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
632: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
633:
634: <dd>
635:
636: <p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
637: except that the text must be such that running the following
638: algorithm results in a conforming document with no
639: <code><a href="#the-noscript-element">noscript</a></code> elements and no <code><a href="#script">script</a></code>
640: elements, and such that no step in the algorithm causes an
641: <a href="#html-parser">HTML parser</a> to flag a <a href="#parse-error">parse error</a>:</p>
642:
643: <ol><li>Remove every <code><a href="#script">script</a></code> element from the
644: document.</li>
645:
646: <li>Make a list of every <code><a href="#the-noscript-element">noscript</a></code> element in the
647: document. For every <code><a href="#the-noscript-element">noscript</a></code> element in that list,
648: perform the following steps:
649:
650: <ol><li>Let the <var title="">parent element</var> be the parent
651: element of the <code><a href="#the-noscript-element">noscript</a></code> element.</li>
652:
653: <li>Take all the children of the <var title="">parent element</var>
654: that come before the <code><a href="#the-noscript-element">noscript</a></code> element, and call these
655: elements <var title="">the before children</var>.</li>
656:
657: <li>Take all the children of the <var title="">parent element</var>
658: that come <em>after</em> the <code><a href="#the-noscript-element">noscript</a></code> element, and
659: call these elements <var title="">the after children</var>.</li>
660:
661: <li>Let <var title="">s</var> be the concatenation of all the
662: <a href="infrastructure.html#text-node">text node</a> children of the <code><a href="#the-noscript-element">noscript</a></code>
663: element.</li>
664:
665: <li>Set the <code title="dom-innerHTML"><a href="apis-in-html-documents.html#dom-innerhtml">innerHTML</a></code>
666: attribute of the <var title="">parent element</var> to the value
667: of <var title="">s</var>. (This, as a side-effect, causes the
668: <code><a href="#the-noscript-element">noscript</a></code> element to be removed from the
669: document.)</li>
670:
671: <li>Insert <var title="">the before children</var> at the start of
672: the <var title="">parent element</var>, preserving their original
673: relative order.</li>
674:
675: <li>Insert <var title="">the after children</var> at the end of the
676: <var title="">parent element</var>, preserving their original
677: relative order.</li>
678:
679: </ol></li>
680:
681: </ol></dd>
682:
683: </dl><p class="note">All these contortions are required because, for
684: historical reasons, the <code><a href="#the-noscript-element">noscript</a></code> element is handled
685: differently by the <a href="#html-parser">HTML parser</a> based on whether <a href="#scripting-flag" title="scripting flag">scripting was enabled or not</a> when the
686: 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
687: documents</a>.</p><p class="note"><strong>The <code><a href="#the-noscript-element">noscript</a></code> element is only
688: effective in <a href="syntax.html#syntax">the HTML syntax</a>, it has no effect in
1.26 mike 689: <a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML syntax</a>.</strong></p><div class="example">
1.11 mike 690:
691: <p>In the following example, a <code><a href="#the-noscript-element">noscript</a></code> element is
692: used to provide fallback for a script.</p>
693:
694: <pre><form action="calcSquare.php">
695: <p>
696: <label for=x>Number</label>:
697: <input id="x" name="x" type="number">
698: </p>
699: <script>
700: var x = document.getElementById('x');
701: var output = document.createElement('p');
702: output.textContent = 'Type a number; it will be squared right then!';
703: x.form.appendChild(output);
704: x.form.onsubmit = function () { return false; }
705: x.oninput = function () {
706: var v = x.valueAsNumber;
707: output.textContent = v + ' squared is ' + v * v;
708: };
709: </script>
710: <noscript>
711: <input type=submit value="Calculate Square">
712: </noscript>
713: </form></pre>
714:
715: <p>When script is disabled, a button appears to do the calculation
716: on the server side. When script is enabled, the value is computed
717: on-the-fly instead.</p>
718:
719: <p>The <code><a href="#the-noscript-element">noscript</a></code> element is a blunt
720: instrument. Sometimes, scripts might be enabled, but for some
721: reason the page's script might fail. For this reason, it's
722: generally better to avoid using <code><a href="#the-noscript-element">noscript</a></code>, and to
723: instead design the script to change the page from being a
724: scriptless page to a scripted page on the fly, as in the next
725: example:</p>
726:
727: <pre><form action="calcSquare.php">
728: <p>
729: <label for=x>Number</label>:
730: <input id="x" name="x" type="number">
731: </p>
732: <strong><input id="submit" type=submit value="Calculate Square"></strong>
733: <script>
734: var x = document.getElementById('x');
735: var output = document.createElement('p');
736: output.textContent = 'Type a number; it will be squared right then!';
737: x.form.appendChild(output);
738: x.form.onsubmit = function () { return false; }
739: x.oninput = function () {
740: var v = x.valueAsNumber;
741: output.textContent = v + ' squared is ' + v * v;
742: };
743: <strong> var submit = document.getElementById('submit');
744: submit.parentNode.removeChild(submit);</strong>
745: </script>
746: </form></pre>
747:
748: <p>The above technique is also useful in XHTML, since
1.26 mike 749: <code><a href="#the-noscript-element">noscript</a></code> is not supported in <a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML
1.11 mike 750: syntax</a>.</p>
751:
752: </div></body></html>
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