Annotation of html5/spec-author-view/constraints.html, revision 1.15
1.1 mike 1: <!doctype html>
1.14 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">
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: i, em { font-style: italic; }
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; }
29: table thead, table tbody { border-bottom: solid; }
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, p.overview { float: right; }
44: pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; position: relative; }
45: pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
46: pre.idl::before { content: "IDL"; font: bold small sans-serif; padding: 0.5em; background: white; position: absolute; top: 0; margin: -1px 0 0 -4em; width: 1.5em; border: thin solid; border-radius: 0 0 0 0.5em }
47: pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
48: pre.css:first-line { color: #AAAA50; }
49: dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #DDFFDD; }
50: hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
51: dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
52: dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
53: dl.domintro dd p { margin: 0.5em 0; }
54: dl.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; }
55: dl.switch { padding-left: 2em; }
56: dl.switch > dt { text-indent: -1.5em; }
57: dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
58: dl.triple { padding: 0 0 0 1em; }
59: dl.triple dt, dl.triple dd { margin: 0; display: inline }
60: dl.triple dt:after { content: ':'; }
61: dl.triple dd:after { content: '\A'; white-space: pre; }
62: .diff-old { text-decoration: line-through; color: silver; background: transparent; }
63: .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
64: a .diff-new { border-bottom: 1px blue solid; }
65:
66: h2 { page-break-before: always; }
67: h1, h2, h3, h4, h5, h6 { page-break-after: avoid; }
68: h1 + h2, hr + h2.no-toc { page-break-before: auto; }
69:
70: p > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]),
71: li > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]), { border-bottom: solid #9999CC; }
72:
73: div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
74: div.head p { margin: 0; }
75: div.head h1 { margin: 0; }
76: div.head .logo { float: right; margin: 0 1em; }
77: div.head .logo img { border: none } /* remove border from top image */
78: div.head dl { margin: 1em 0; }
79: div.head p.copyright, div.head p.alt { font-size: x-small; font-style: oblique; margin: 0; }
80:
81: body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
82: body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
83: body > .toc > li > * { margin-bottom: 0.5em; }
84: body > .toc > li > * > li > * { margin-bottom: 0.25em; }
85: .toc, .toc li { list-style: none; }
86:
87: .brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
88: .brief li { margin: 0; padding: 0; }
89: .brief li p { margin: 0; padding: 0; }
90:
91: .category-list { margin-top: -0.75em; margin-bottom: 1em; line-height: 1.5; }
92: .category-list::before { content: '\21D2\A0'; font-size: 1.2em; font-weight: 900; }
93: .category-list li { display: inline; }
94: .category-list li:not(:last-child)::after { content: ', '; }
95: .category-list li > span, .category-list li > a { text-transform: lowercase; }
96: .category-list li * { text-transform: none; } /* don't affect <code> nested in <a> */
97:
98: .XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
99: .XXX > :first-child { margin-top: 0; }
100: p .XXX { line-height: 3em; }
101: .annotation { border: solid thin black; background: #0C479D; color: white; position: relative; margin: 8px 0 20px 0; }
102: .annotation:before { position: absolute; left: 0; top: 0; width: 100%; height: 100%; margin: 6px -6px -6px 6px; background: #333333; z-index: -1; content: ''; }
103: .annotation :link, .annotation :visited { color: inherit; }
104: .annotation :link:hover, .annotation :visited:hover { background: transparent; }
105: .annotation span { border: none ! important; }
106: .note { color: green; background: transparent; font-family: sans-serif; }
107: .warning { color: red; background: transparent; }
108: .note, .warning { font-weight: bolder; font-style: italic; }
109: .note em, .warning em, .note i, .warning i { font-style: normal; }
110: p.note, div.note { padding: 0.5em 2em; }
111: span.note { padding: 0 2em; }
112: .note p:first-child, .warning p:first-child { margin-top: 0; }
113: .note p:last-child, .warning p:last-child { margin-bottom: 0; }
114: .warning:before { font-style: normal; }
115: p.note:before { content: 'Note: '; }
116: p.warning:before { content: '\26A0 Warning! '; }
117:
118: .bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
119: .bookkeeping { font-size: 0.8em; margin: 2em 0; }
120: .bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }
121: .bookkeeping dt { margin: 0.5em 2em 0; }
122: .bookkeeping dd { margin: 0 3em 0.5em; }
123:
124: h4 { position: relative; z-index: 3; }
125: h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
126: .element {
127: background: #EEEEFF;
128: color: black;
129: margin: 0 0 1em 0.15em;
130: padding: 0 1em 0.25em 0.75em;
131: border-left: solid #9999FF 0.25em;
132: position: relative;
133: z-index: 1;
134: }
135: .element:before {
136: position: absolute;
137: z-index: 2;
138: top: 0;
139: left: -1.15em;
140: height: 2em;
141: width: 0.9em;
142: background: #EEEEFF;
143: content: ' ';
144: border-style: none none solid solid;
145: border-color: #9999FF;
146: border-width: 0.25em;
147: }
148:
149: .example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
150: td > .example:only-child { margin: 0 0 0 0.1em; }
151:
152: ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
153: ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
154: ul.domTree li li { list-style: none; }
155: 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; }
156: 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; }
157: ul.domTree span { font-style: italic; font-family: serif; }
158: ul.domTree .t1 code { color: purple; font-weight: bold; }
159: ul.domTree .t2 { font-style: normal; font-family: monospace; }
160: ul.domTree .t2 .name { color: black; font-weight: bold; }
161: ul.domTree .t2 .value { color: blue; font-weight: normal; }
162: ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
163: ul.domTree .t7 code, .domTree .t8 code { color: green; }
164: ul.domTree .t10 code { color: teal; }
165:
166: body.dfnEnabled dfn { cursor: pointer; }
167: .dfnPanel {
168: display: inline;
169: position: absolute;
170: z-index: 10;
171: height: auto;
172: width: auto;
173: padding: 0.5em 0.75em;
174: font: small sans-serif, Droid Sans Fallback;
175: background: #DDDDDD;
176: color: black;
177: border: outset 0.2em;
178: }
179: .dfnPanel * { margin: 0; padding: 0; font: inherit; text-indent: 0; }
180: .dfnPanel :link, .dfnPanel :visited { color: black; }
181: .dfnPanel p { font-weight: bolder; }
182: .dfnPanel * + p { margin-top: 0.25em; }
183: .dfnPanel li { list-style-position: inside; }
184:
185: #configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
186: #configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
187: #configUI p label { display: block; }
188: #configUI #updateUI, #configUI .loginUI { text-align: center; }
189: #configUI input[type=button] { display: block; margin: auto; }
190:
191: fieldset { margin: 1em; padding: 0.5em 1em; }
192: fieldset > legend + * { margin-top: 0; }
193: fieldset > :last-child { margin-bottom: 0; }
194: fieldset p { margin: 0.5em 0; }
195:
196: </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">
1.1 mike 197:
198: .applies thead th > * { display: block; }
199: .applies thead code { display: block; }
200: .applies tbody th { whitespace: nowrap; }
201: .applies td { text-align: center; }
202: .applies .yes { background: yellow; }
203:
204: .matrix, .matrix td { border: hidden; text-align: right; }
205: .matrix { margin-left: 2em; }
206:
207: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
208: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
209: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
210:
211: td.eg { border-width: thin; text-align: center; }
212:
213: #table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
214: #table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
215: #table-example-1 caption { padding-bottom: 0.5em; }
216: #table-example-1 thead, #table-example-1 tbody { border: none; }
217: #table-example-1 th, #table-example-1 td { border: solid thin; }
218: #table-example-1 th { font-weight: normal; }
219: #table-example-1 td { border-style: none solid; vertical-align: top; }
220: #table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
221: #table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
222: #table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
223: #table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
224: #table-example-1 tbody td:first-child::after { content: leader(". "); }
225: #table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
226: #table-example-1 tbody td:first-child + td { width: 10em; }
227: #table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
228: #table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
229:
230: .apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
231: .apple-table-examples * { font-family: "Times", serif; }
232: .apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
233: .apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
234: .apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
235: .apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
236: .apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
237: .apple-table-examples td { text-align: right; vertical-align: top; }
238: .apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
239: .apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
240: .apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
241: .apple-table-examples sup { line-height: 0; }
242:
243: .details-example img { vertical-align: top; }
244:
245: #base64-table {
246: white-space: nowrap;
247: font-size: 0.6em;
248: column-width: 6em;
249: column-count: 5;
250: column-gap: 1em;
251: -moz-column-width: 6em;
252: -moz-column-count: 5;
253: -moz-column-gap: 1em;
254: -webkit-column-width: 6em;
255: -webkit-column-count: 5;
256: -webkit-column-gap: 1em;
257: }
258: #base64-table thead { display: none; }
259: #base64-table * { border: none; }
260: #base64-table tbody td:first-child:after { content: ':'; }
261: #base64-table tbody td:last-child { text-align: right; }
262:
263: #named-character-references-table {
264: white-space: nowrap;
265: font-size: 0.6em;
266: column-width: 30em;
267: column-gap: 1em;
268: -moz-column-width: 30em;
269: -moz-column-gap: 1em;
270: -webkit-column-width: 30em;
271: -webkit-column-gap: 1em;
272: }
273: #named-character-references-table > table > tbody > tr > td:first-child + td,
274: #named-character-references-table > table > tbody > tr > td:last-child { text-align: center; }
275: #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; }
276: #named-character-references-table > table > tbody > tr#entity-CounterClockwiseContourIntegral > td:first-child { font-size: 0.5em; }
277:
278: .glyph.control { color: red; }
279:
280: @font-face {
281: font-family: 'Essays1743';
282: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743.ttf');
283: }
284: @font-face {
285: font-family: 'Essays1743';
286: font-weight: bold;
287: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Bold.ttf');
288: }
289: @font-face {
290: font-family: 'Essays1743';
291: font-style: italic;
292: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-Italic.ttf');
293: }
294: @font-face {
295: font-family: 'Essays1743';
296: font-style: italic;
297: font-weight: bold;
298: src: url('http://www.whatwg.org/specs/web-apps/current-work/fonts/Essays1743-BoldItalic.ttf');
299: }
300:
301: </style><script type="text/javascript">
302: function getCookie(name) {
303: var params = location.search.substr(1).split("&");
304: for (var index = 0; index < params.length; index++) {
305: if (params[index] == name)
306: return "1";
307: var data = params[index].split("=");
308: if (data[0] == name)
309: return unescape(data[1]);
310: }
311: var cookies = document.cookie.split("; ");
312: for (var index = 0; index < cookies.length; index++) {
313: var data = cookies[index].split("=");
314: if (data[0] == name)
315: return unescape(data[1]);
316: }
317: return null;
318: }
319: function load(script) {
320: var e = document.createElement('script');
321: e.setAttribute('src', script + '?' + encodeURIComponent(location) + '&' + encodeURIComponent(document.referrer));
322: document.body.appendChild(e);
323: }
324: function init() {
325: if (location.search == '?slow-browser')
326: return;
327: var configUI = document.createElement('div');
328: configUI.id = 'configUI';
329: document.body.appendChild(configUI);
330: if (document.getElementById('head'))
331: load('toc.js');
332: load('dfn.js');
333: if (getCookie('profile') == '1')
334: document.getElementsByTagName('h2')[0].textContent += '; load: ' + (new Date() - loadTimer) + 'ms';
335: fixBrokenLink();
336: }
337: </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">
338: <link href="Overview.html#contents" rel="contents" title="Table of contents">
339: <link href="form-submission.html" rel="next" title="4.10.22 Form submission">
1.15 ! mike 340: <body class="split chapter" onload="fixBrokenLink();"><div class="head" id="head">
1.1 mike 341: <div aria-haspopup="true" id="jumpIndexA-button" role="button" tabindex="0">jump
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1.1 mike 343: <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>
344:
345: <h1>HTML5: Edition for Web Authors</h1>
346:
347: </div><div class="prev_next">
348: <a href="textFieldSelection.html">← 4.10.20 APIs for the text field selections</a> –
349: <a href="Overview.html#contents">Table of contents</a> –
350: <a href="form-submission.html">4.10.22 Form submission →</a>
351: <ol class="toc"><li><ol><li><ol><li><a href="constraints.html#constraints"><span class="secno">4.10.21 </span>Constraints</a>
352: <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>
353:
354: <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>
355:
356: <dd>
357:
358: <p>Returns true if the element will be validated when the form is submitted; false otherwise.</p>
359:
360: </dd>
361:
362: <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>
363:
364: <dd>
365:
366: <p>Sets a custom error, so that the element would fail to
367: validate. The given message is the message to be shown to the user
368: when reporting the problem to the user.</p>
369:
370: <p>If the argument is the empty string, clears the custom error.</p>
371:
372: </dd>
373:
374: <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>
375:
376: <dd>
377:
378: <p>Returns true if the element has no value but is a required field; false otherwise.</p>
379:
380: </dd>
381:
382: <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>
383:
384: <dd>
385:
386: <p>Returns true if the element's value is not in the correct syntax; false otherwise.</p>
387:
388: </dd>
389:
390: <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>
391:
392: <dd>
393:
394: <p>Returns true if the element's value doesn't match the provided pattern; false otherwise.</p>
395:
396: </dd>
397:
398: <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>
399:
400: <dd>
401:
402: <p>Returns true if the element's value is longer than the provided maximum length; false otherwise.</p>
403:
404: </dd>
405:
406: <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>
407:
408: <dd>
409:
410: <p>Returns true if the element's value is lower than the provided minimum; false otherwise.</p>
411:
412: </dd>
413:
414: <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>
415:
416: <dd>
417:
418: <p>Returns true if the element's value is higher than the provided maximum; false otherwise.</p>
419:
420: </dd>
421:
422: <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>
423:
424: <dd>
425:
426: <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>
427:
428: </dd>
429:
430: <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>
431:
432: <dd>
433:
434: <p>Returns true if the element has a custom error; false otherwise.</p>
435:
436: </dd>
437:
438: <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>
439:
440: <dd>
441:
442: <p>Returns true if the element's value has no validity problems; false otherwise.</p>
443:
444: </dd>
445:
446: <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>
447:
448: <dd>
449:
450: <p>Returns true if the element's value has no validity problems;
451: false otherwise. Fires an <code title="event-invalid">invalid</code> event at the element in the
452: latter case.</p>
453:
454: </dd>
455:
456: <dt><var title="">element</var> . <code id="dom-cva-validationmessage" title="dom-cva-validationMessage"><a href="#dom-cva-validationmessage">validationMessage</a></code></dt>
457:
458: <dd>
459:
460: <p>Returns the error message that would be shown to the user if
461: the element was to be checked for validity.</p>
462:
463: </dd>
464:
465: </dl><div class="example">
466:
467: <p>In the following example, a script checks the value of a form
468: control each time it is edited, and whenever it is not a valid
469: value, uses the <code title="dom-cva-setCustomValidity"><a href="#dom-cva-setcustomvalidity">setCustomValidity()</a></code> method
470: to set an appropriate message.</p>
471:
472: <pre><label>Feeling: <input name=f type="text" oninput="check(this)"></label>
473: <script>
474: function check(input) {
475: if (input.value == "good" ||
476: input.value == "fine" ||
477: input.value == "tired") {
478: input.setCustomValidity('"' + input.value + '" is not a feeling.');
479: } else {
480: // input is fine -- reset the error message
481: input.setCustomValidity('');
482: }
483: }
484: </script></pre>
485:
486: </div>
487: <p>The <dfn aria-haspopup="true" id="dom-cva-validity" role="button" tabindex="0"><code>validity</code></dfn>
1.12 mike 488: attribute must return a <code><a class="full-spec-link" href="http://dev.w3.org/html5/spec/constraints.html#validitystate" title='Read about this "ValidityState" reference in the full HTML5 spec.'>ValidityState</a></code> object that
489: represents the <a class="full-spec-link" href="http://dev.w3.org/html5/spec/constraints.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 490: object is <a href="infrastructure.html#live" id="live_0">live</a>, and the same object must be returned
1.1 mike 491: 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>
492: <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
493: validation. Client-side validation can be intentionally bypassed by
494: hostile users, and unintentionally bypassed by users of older user
495: agents or automated tools that do not implement these features. The
496: constraint validation features are only intended to improve the user
497: experience, not to provide any kind of security mechanism.
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