Annotation of html5/spec-author-view/constraints.html, revision 1.3
1.1 mike 1: <!doctype html>
1.2 mike 2: <html lang="en-US-x-Hixie"><meta content="text/html; charset=utf-8" http-equiv="Content-Type"><title>4.10.21 Constraints — HTML5: Edition for Web Authors</title><link href="whatwg.css" rel="stylesheet"><style type="text/css">
1.1 mike 3: pre { margin-left: 2em; white-space: pre-wrap; }
4: h2 { margin: 3em 0 1em 0; }
5: h3 { margin: 2.5em 0 1em 0; }
6: h4 { margin: 2.5em 0 0.75em 0; }
7: h5, h6 { margin: 2.5em 0 1em; }
8: h1 + h2, h1 + h2 + h2 { margin: 0.75em 0 0.75em; }
9: h2 + h3, h3 + h4, h4 + h5, h5 + h6 { margin-top: 0.5em; }
10: p { margin: 1em 0; }
11: hr:not(.top) { display: block; background: none; border: none; padding: 0; margin: 2em 0; height: auto; }
12: dl, dd { margin-top: 0; margin-bottom: 0; }
13: dt { margin-top: 0.75em; margin-bottom: 0.25em; clear: left; }
14: dt + dt { margin-top: 0; }
15: dd dt { margin-top: 0.25em; margin-bottom: 0; }
16: dd p { margin-top: 0; }
17: dd dl + p { margin-top: 1em; }
18: dd table + p { margin-top: 1em; }
19: p + * > li, dd li { margin: 1em 0; }
20: dt, dfn { font-weight: bold; font-style: normal; }
21: dt dfn { font-style: italic; }
22: pre, code { font-size: inherit; font-family: monospace; font-variant: normal; }
23: pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
24: pre em { font-weight: bolder; font-style: normal; }
25: @media screen { code { color: orangered; } code :link, code :visited { color: inherit; } }
26: var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
27: table { border-collapse: collapse; border-style: hidden hidden none hidden; }
28: table thead, table tbody { border-bottom: solid; }
29: table tbody th:first-child { border-left: solid; }
30: table tbody th { text-align: left; }
31: table td, table th { border-left: solid; border-right: solid; border-bottom: solid thin; vertical-align: top; padding: 0.2em; }
32: blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }
33:
34: .bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
35: .matrix, .matrix td { border: none; text-align: right; }
36: .matrix { margin-left: 2em; }
37: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
38: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
39: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
40:
41: .toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
42: img.extra { float: right; }
43: pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; }
44: pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
45: pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
46: pre.css:first-line { color: #AAAA50; }
47: dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #DDFFDD; }
48: hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
49: dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
50: dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
51: dl.domintro dd p { margin: 0.5em 0; }
52: dl.switch { padding-left: 2em; }
53: dl.switch > dt { text-indent: -1.5em; }
54: dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
55: dl.triple { padding: 0 0 0 1em; }
56: dl.triple dt, dl.triple dd { margin: 0; display: inline }
57: dl.triple dt:after { content: ':'; }
58: dl.triple dd:after { content: '\A'; white-space: pre; }
59: .diff-old { text-decoration: line-through; color: silver; background: transparent; }
60: .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
61: a .diff-new { border-bottom: 1px blue solid; }
62:
63: h2 { page-break-before: always; }
64: h1, h2, h3, h4, h5, h6 { page-break-after: avoid; }
65: h1 + h2, hr + h2.no-toc { page-break-before: auto; }
66:
67: p > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]),
68: li > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]), { 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: .bookkeeping dt { margin: 0.5em 2em 0; }
118: .bookkeeping dd { margin: 0 3em 0.5em; }
119:
120: h4 { position: relative; z-index: 3; }
121: h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
122: .element {
123: background: #EEEEFF;
124: color: black;
125: margin: 0 0 1em 0.15em;
126: padding: 0 1em 0.25em 0.75em;
127: border-left: solid #9999FF 0.25em;
128: position: relative;
129: z-index: 1;
130: }
131: .element:before {
132: position: absolute;
133: z-index: 2;
134: top: 0;
135: left: -1.15em;
136: height: 2em;
137: width: 0.9em;
138: background: #EEEEFF;
139: content: ' ';
140: border-style: none none solid solid;
141: border-color: #9999FF;
142: border-width: 0.25em;
143: }
144:
145: .example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
146: td > .example:only-child { margin: 0 0 0 0.1em; }
147:
148: ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
149: ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
150: ul.domTree li li { list-style: none; }
151: 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; }
152: 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; }
153: ul.domTree span { font-style: italic; font-family: serif; }
154: ul.domTree .t1 code { color: purple; font-weight: bold; }
155: ul.domTree .t2 { font-style: normal; font-family: monospace; }
156: ul.domTree .t2 .name { color: black; font-weight: bold; }
157: ul.domTree .t2 .value { color: blue; font-weight: normal; }
158: ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
159: ul.domTree .t7 code, .domTree .t8 code { color: green; }
160: ul.domTree .t10 code { color: teal; }
161:
162: body.dfnEnabled dfn { cursor: pointer; }
163: .dfnPanel {
164: display: inline;
165: position: absolute;
166: z-index: 10;
167: height: auto;
168: width: auto;
169: padding: 0.5em 0.75em;
170: font: small sans-serif, Droid Sans Fallback;
171: background: #DDDDDD;
172: color: black;
173: border: outset 0.2em;
174: }
175: .dfnPanel * { margin: 0; padding: 0; font: inherit; text-indent: 0; }
176: .dfnPanel :link, .dfnPanel :visited { color: black; }
177: .dfnPanel p { font-weight: bolder; }
178: .dfnPanel * + p { margin-top: 0.25em; }
179: .dfnPanel li { list-style-position: inside; }
180:
181: #configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
182: #configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
183: #configUI p label { display: block; }
184: #configUI #updateUI, #configUI .loginUI { text-align: center; }
185: #configUI input[type=button] { display: block; margin: auto; }
186:
187: fieldset { margin: 1em; padding: 0.5em 1em; }
188: fieldset > legend + * { margin-top: 0; }
189: fieldset > :last-child { margin-bottom: 0; }
190: fieldset p { margin: 0.5em 0; }
191:
192: </style><link href="style.css" rel="stylesheet"><link href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet" type="text/css"><script src="link-fixup.js" type="text/javascript"></script><style type="text/css">
193:
194: .applies thead th > * { display: block; }
195: .applies thead code { display: block; }
196: .applies tbody th { whitespace: nowrap; }
197: .applies td { text-align: center; }
198: .applies .yes { background: yellow; }
199:
200: .matrix, .matrix td { border: hidden; text-align: right; }
201: .matrix { margin-left: 2em; }
202:
203: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
204: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
205: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
206:
207: td.eg { border-width: thin; text-align: center; }
208:
209: #table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
210: #table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
211: #table-example-1 caption { padding-bottom: 0.5em; }
212: #table-example-1 thead, #table-example-1 tbody { border: none; }
213: #table-example-1 th, #table-example-1 td { border: solid thin; }
214: #table-example-1 th { font-weight: normal; }
215: #table-example-1 td { border-style: none solid; vertical-align: top; }
216: #table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
217: #table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
218: #table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
219: #table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
220: #table-example-1 tbody td:first-child::after { content: leader(". "); }
221: #table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
222: #table-example-1 tbody td:first-child + td { width: 10em; }
223: #table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
224: #table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
225:
226: .apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
227: .apple-table-examples * { font-family: "Times", serif; }
228: .apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
229: .apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
230: .apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
231: .apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
232: .apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
233: .apple-table-examples td { text-align: right; vertical-align: top; }
234: .apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
235: .apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
236: .apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
237: .apple-table-examples sup { line-height: 0; }
238:
239: .details-example img { vertical-align: top; }
240:
241: #base64-table {
242: white-space: nowrap;
243: font-size: 0.6em;
244: column-width: 6em;
245: column-count: 5;
246: column-gap: 1em;
247: -moz-column-width: 6em;
248: -moz-column-count: 5;
249: -moz-column-gap: 1em;
250: -webkit-column-width: 6em;
251: -webkit-column-count: 5;
252: -webkit-column-gap: 1em;
253: }
254: #base64-table thead { display: none; }
255: #base64-table * { border: none; }
256: #base64-table tbody td:first-child:after { content: ':'; }
257: #base64-table tbody td:last-child { text-align: right; }
258:
259: #named-character-references-table {
260: white-space: nowrap;
261: font-size: 0.6em;
262: column-width: 30em;
263: column-gap: 1em;
264: -moz-column-width: 30em;
265: -moz-column-gap: 1em;
266: -webkit-column-width: 30em;
267: -webkit-column-gap: 1em;
268: }
269: #named-character-references-table > table > tbody > tr > td:first-child + td,
270: #named-character-references-table > table > tbody > tr > td:last-child { text-align: center; }
271: #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; }
272: #named-character-references-table > table > tbody > tr#entity-CounterClockwiseContourIntegral > td:first-child { font-size: 0.5em; }
273:
274: .glyph.control { color: red; }
275:
276: @font-face {
277: font-family: 'Essays1743';
278: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743.ttf');
279: }
280: @font-face {
281: font-family: 'Essays1743';
282: font-weight: bold;
283: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Bold.ttf');
284: }
285: @font-face {
286: font-family: 'Essays1743';
287: font-style: italic;
288: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Italic.ttf');
289: }
290: @font-face {
291: font-family: 'Essays1743';
292: font-style: italic;
293: font-weight: bold;
294: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-BoldItalic.ttf');
295: }
296:
297: </style><script type="text/javascript">
298: function getCookie(name) {
299: var params = location.search.substr(1).split("&");
300: for (var index = 0; index < params.length; index++) {
301: if (params[index] == name)
302: return "1";
303: var data = params[index].split("=");
304: if (data[0] == name)
305: return unescape(data[1]);
306: }
307: var cookies = document.cookie.split("; ");
308: for (var index = 0; index < cookies.length; index++) {
309: var data = cookies[index].split("=");
310: if (data[0] == name)
311: return unescape(data[1]);
312: }
313: return null;
314: }
315: function load(script) {
316: var e = document.createElement('script');
317: e.setAttribute('src', script + '?' + encodeURIComponent(location) + '&' + encodeURIComponent(document.referrer));
318: document.body.appendChild(e);
319: }
320: function init() {
321: if (location.search == '?slow-browser')
322: return;
323: var configUI = document.createElement('div');
324: configUI.id = 'configUI';
325: document.body.appendChild(configUI);
326: if (document.getElementById('head'))
327: load('toc.js');
328: load('dfn.js');
329: if (getCookie('profile') == '1')
330: document.getElementsByTagName('h2')[0].textContent += '; load: ' + (new Date() - loadTimer) + 'ms';
331: fixBrokenLink();
332: }
333: </script><script src="dfn.js" type="text/javascript"></script><script src="toc.js" type="text/javascript"></script><link href="textFieldSelection.html" rel="prev" title="4.10.20 APIs for the text field selections">
334: <link href="Overview.html#contents" rel="contents" title="Table of contents">
335: <link href="form-submission.html" rel="next" title="4.10.22 Form submission">
336: <body class="split chapter"><div class="head" id="head">
337: <div aria-haspopup="true" id="jumpIndexA-button" role="button" tabindex="0">jump
338: <div id="jumpIndexA"><ul><li><a class="noindex" href="the-a-element.html#the-a-element">a</a><a class="noindex" href="the-abbr-element.html#the-abbr-element">abbr</a><a class="noindex" href="the-address-element.html#the-address-element">address</a><a class="noindex" href="the-area-element.html#the-area-element">area</a><a class="noindex" href="the-article-element.html#the-article-element">article</a><a class="noindex" href="the-aside-element.html#the-aside-element">aside</a><a class="noindex" href="the-audio-element.html#the-audio-element">audio</a></ul><ul><li><a class="noindex" href="the-b-element.html#the-b-element">b</a><a class="noindex" href="the-base-element.html#the-base-element">base</a><a class="noindex" href="the-bdi-element.html#the-bdi-element">bdi</a><a class="noindex" href="the-bdo-element.html#the-bdo-element">bdo</a><a class="noindex" href="the-blockquote-element.html#the-blockquote-element">blockquote</a><a class="noindex" 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class="noindex" href="the-details-element.html#the-details-element">details</a><a class="noindex" href="the-dfn-element.html#the-dfn-element">dfn</a><a class="noindex" href="the-div-element.html#the-div-element">div</a><a class="noindex" href="the-dl-element.html#the-dl-element">dl</a><a class="noindex" href="the-dt-element.html#the-dt-element">dt</a></ul><ul><li><a class="noindex" href="the-em-element.html#the-em-element">em</a><a class="noindex" href="the-embed-element.html#the-embed-element">embed</a><a class="noindex" href="the-fieldset-element.html#the-fieldset-element">fieldset</a><a class="noindex" href="the-figcaption-element.html#the-figcaption-element">figcaption</a><a class="noindex" href="the-figure-element.html#the-figure-element">figure</a><a class="noindex" href="the-footer-element.html#the-footer-element">footer</a><a class="noindex" href="the-form-element.html#the-form-element">form</a></ul><ul><li><a class="noindex" 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339: <script src="jump-indexes.js"></script><p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
340:
341: <h1>HTML5: Edition for Web Authors</h1>
342:
343: </div><div class="prev_next">
344: <a href="textFieldSelection.html">← 4.10.20 APIs for the text field selections</a> –
345: <a href="Overview.html#contents">Table of contents</a> –
346: <a href="form-submission.html">4.10.22 Form submission →</a>
347: <ol class="toc"><li><ol><li><ol><li><a href="constraints.html#constraints"><span class="secno">4.10.21 </span>Constraints</a>
348: <ol><li><a href="constraints.html#definitions"><span class="secno">4.10.21.1 </span>Definitions</a><li><a href="constraints.html#the-constraint-validation-api" id="4.10.21.2-the-constraint-validation-api"><span class="secno">4.10.21.2 </span>The constraint validation API</a><li><a href="constraints.html#security-forms"><span class="secno">4.10.21.3 </span>Security</a></ol></ol></ol></ol></div>
349:
350: <h4 id="constraints"><span class="secno">4.10.21 </span>Constraints</h4><h5 id="definitions"><span class="secno">4.10.21.1 </span>Definitions</h5><h5 id="the-constraint-validation-api"><span class="secno">4.10.21.2 </span>The <dfn aria-haspopup="true" role="button" tabindex="0">constraint validation API</dfn></h5><dl class="domintro"><dt><var title="">element</var> . <code id="dom-cva-willvalidate" title="dom-cva-willValidate"><a href="#dom-cva-willvalidate">willValidate</a></code></dt>
351:
352: <dd>
353:
354: <p>Returns true if the element will be validated when the form is submitted; false otherwise.</p>
355:
356: </dd>
357:
358: <dt><var title="">element</var> . <code id="dom-cva-setcustomvalidity" title="dom-cva-setCustomValidity"><a href="#dom-cva-setcustomvalidity">setCustomValidity</a></code>(<var title="">message</var>)</dt>
359:
360: <dd>
361:
362: <p>Sets a custom error, so that the element would fail to
363: validate. The given message is the message to be shown to the user
364: when reporting the problem to the user.</p>
365:
366: <p>If the argument is the empty string, clears the custom error.</p>
367:
368: </dd>
369:
370: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity">validity</a></code> . <code id="dom-validitystate-valuemissing" title="dom-validitystate-valueMissing"><a href="#dom-validitystate-valuemissing">valueMissing</a></code></dt>
371:
372: <dd>
373:
374: <p>Returns true if the element has no value but is a required field; false otherwise.</p>
375:
376: </dd>
377:
378: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_0">validity</a></code> . <code id="dom-validitystate-typemismatch" title="dom-validitystate-typeMismatch"><a href="#dom-validitystate-typemismatch">typeMismatch</a></code></dt>
379:
380: <dd>
381:
382: <p>Returns true if the element's value is not in the correct syntax; false otherwise.</p>
383:
384: </dd>
385:
386: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_1">validity</a></code> . <code id="dom-validitystate-patternmismatch" title="dom-validitystate-patternMismatch"><a href="#dom-validitystate-patternmismatch">patternMismatch</a></code></dt>
387:
388: <dd>
389:
390: <p>Returns true if the element's value doesn't match the provided pattern; false otherwise.</p>
391:
392: </dd>
393:
394: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_2">validity</a></code> . <code id="dom-validitystate-toolong" title="dom-validitystate-tooLong"><a href="#dom-validitystate-toolong">tooLong</a></code></dt>
395:
396: <dd>
397:
398: <p>Returns true if the element's value is longer than the provided maximum length; false otherwise.</p>
399:
400: </dd>
401:
402: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_3">validity</a></code> . <code id="dom-validitystate-rangeunderflow" title="dom-validitystate-rangeUnderflow"><a href="#dom-validitystate-rangeunderflow">rangeUnderflow</a></code></dt>
403:
404: <dd>
405:
406: <p>Returns true if the element's value is lower than the provided minimum; false otherwise.</p>
407:
408: </dd>
409:
410: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_4">validity</a></code> . <code id="dom-validitystate-rangeoverflow" title="dom-validitystate-rangeOverflow"><a href="#dom-validitystate-rangeoverflow">rangeOverflow</a></code></dt>
411:
412: <dd>
413:
414: <p>Returns true if the element's value is higher than the provided maximum; false otherwise.</p>
415:
416: </dd>
417:
418: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_5">validity</a></code> . <code id="dom-validitystate-stepmismatch" title="dom-validitystate-stepMismatch"><a href="#dom-validitystate-stepmismatch">stepMismatch</a></code></dt>
419:
420: <dd>
421:
422: <p>Returns true if the element's value doesn't fit the rules given by the <code title="attr-input-step"><a href="common-input-element-attributes.html#attr-input-step" id="step_36">step</a></code> attribute; false otherwise.</p>
423:
424: </dd>
425:
426: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_6">validity</a></code> . <code id="dom-validitystate-customerror" title="dom-validitystate-customError"><a href="#dom-validitystate-customerror">customError</a></code></dt>
427:
428: <dd>
429:
430: <p>Returns true if the element has a custom error; false otherwise.</p>
431:
432: </dd>
433:
434: <dt><var title="">element</var> . <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_7">validity</a></code> . <code id="dom-validitystate-valid" title="dom-validitystate-valid"><a href="#dom-validitystate-valid">valid</a></code></dt>
435:
436: <dd>
437:
438: <p>Returns true if the element's value has no validity problems; false otherwise.</p>
439:
440: </dd>
441:
442: <dt><var title="">valid</var> = <var title="">element</var> . <code id="dom-cva-checkvalidatity" title="dom-cva-checkValidatity"><a href="#dom-cva-checkvalidatity">checkValidity</a></code>()</dt>
443:
444: <dd>
445:
446: <p>Returns true if the element's value has no validity problems;
447: false otherwise. Fires an <code title="event-invalid">invalid</code> event at the element in the
448: latter case.</p>
449:
450: </dd>
451:
452: <dt><var title="">element</var> . <code id="dom-cva-validationmessage" title="dom-cva-validationMessage"><a href="#dom-cva-validationmessage">validationMessage</a></code></dt>
453:
454: <dd>
455:
456: <p>Returns the error message that would be shown to the user if
457: the element was to be checked for validity.</p>
458:
459: </dd>
460:
461: </dl><div class="example">
462:
463: <p>In the following example, a script checks the value of a form
464: control each time it is edited, and whenever it is not a valid
465: value, uses the <code title="dom-cva-setCustomValidity"><a href="#dom-cva-setcustomvalidity">setCustomValidity()</a></code> method
466: to set an appropriate message.</p>
467:
468: <pre><label>Feeling: <input name=f type="text" oninput="check(this)"></label>
469: <script>
470: function check(input) {
471: if (input.value == "good" ||
472: input.value == "fine" ||
473: input.value == "tired") {
474: input.setCustomValidity('"' + input.value + '" is not a feeling.');
475: } else {
476: // input is fine -- reset the error message
477: input.setCustomValidity('');
478: }
479: }
480: </script></pre>
481:
482: </div>
483: <p>The <dfn aria-haspopup="true" id="dom-cva-validity" role="button" tabindex="0"><code>validity</code></dfn>
484: attribute must return a <code><a class="full-spec-link" href="http://dev.w3.org/html5/spec/association-of-controls-and-forms.html#validitystate" title='Read about this "ValidityState" reference in the full HTML5 spec.'>ValidityState</a></code> object that
485: represents the <a class="full-spec-link" href="http://dev.w3.org/html5/spec/association-of-controls-and-forms.html#validity-states" title='Read about this "validity states" reference in the full HTML5 spec.'>validity states</a> of the element. This
1.3 ! mike 486: object is <a href="infrastructure.html#live" id="live_0">live</a>, and the same object must be returned
1.1 mike 487: each time the element's <code title="dom-cva-validity"><a href="#dom-cva-validity" id="validity_8">validity</a></code> attribute is retrieved.</p>
488: <h5 id="security-forms"><span class="secno">4.10.21.3 </span>Security</h5><p id="security-0">Servers should not rely on client-side
489: validation. Client-side validation can be intentionally bypassed by
490: hostile users, and unintentionally bypassed by users of older user
491: agents or automated tools that do not implement these features. The
492: constraint validation features are only intended to improve the user
493: experience, not to provide any kind of security mechanism.
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