--- title: HTMLSelectElement.checkValidity() slug: Web/API/HTMLSelectElement/checkValidity translation_of: Web/API/HTMLSelectElement/checkValidity --- <div>{{ APIRef("HTML DOM") }}</div> <p><code><strong>HTMLSelectElement.checkValidity()</strong></code> 会检查元素是否有任何输入约束条件,并且检查值是否符合约束条件. 如果值是不符合约束条件的, 浏览器就会在该元素上触发一个可以撤销的 {{event("invalid")}} 事件, 然后返回 <code>false</code>.</p> <h2 id="Syntax">Syntax</h2> <pre class="eval language-html"><code class="language-html">var <em>result</em> = <em>selectElt</em>.checkValidity();</code></pre> <h2 id="Specifications">Specifications</h2> <table class="standard-table"> <tbody> <tr> <th scope="col">Specification</th> <th scope="col">Status</th> <th scope="col">Comment</th> </tr> <tr> <td>{{SpecName('HTML WHATWG', '#dom-cva-checkvalidity', 'HTMLSelectElement.checkValidity()')}}</td> <td>{{Spec2('HTML WHATWG')}}</td> <td>No change since the latest snapshot, {{SpecName('HTML5 W3C')}}.</td> </tr> <tr> <td>{{SpecName('HTML5 W3C', 'forms.html#dom-cva-checkvalidity', 'HTMLSelectElement.checkValidity()')}}</td> <td>{{Spec2('HTML5 W3C')}}</td> <td>Initial definition, snapshot of {{SpecName('HTML WHATWG')}}</td> </tr> </tbody> </table> <h2 id="Browser_compatibility">Browser compatibility</h2> <div>{{CompatibilityTable}}</div> <div id="compat-desktop"> <table class="compat-table"> <tbody> <tr> <th>Feature</th> <th>Chrome</th> <th>Edge</th> <th>Firefox (Gecko)</th> <th>Internet Explorer</th> <th>Opera</th> <th>Safari (WebKit)</th> </tr> <tr> <td>Basic support</td> <td>{{CompatVersionUnknown}}</td> <td>{{CompatVersionUnknown}}</td> <td>{{CompatGeckoDesktop(2.0)}}</td> <td>10</td> <td>{{CompatVersionUnknown}}</td> <td>{{CompatVersionUnknown}}</td> </tr> </tbody> </table> </div> <div id="compat-mobile"> <table class="compat-table"> <tbody> <tr> <th>Feature</th> <th>Android</th> <th>Chrome</th> <th>Edge</th> <th>Firefox Mobile (Gecko)</th> <th>Firefox OS</th> <th>IE Phone</th> <th>Opera Mobile</th> <th>Safari Mobile</th> </tr> <tr> <td>Basic support</td> <td>{{CompatUnknown}}</td> <td>{{CompatVersionUnknown}}</td> <td>{{CompatVersionUnknown}}</td> <td>{{CompatGeckoMobile(2.0)}}</td> <td>1.0</td> <td>{{CompatUnknown}}</td> <td>{{CompatUnknown}}</td> <td>{{CompatVersionUnknown}}</td> </tr> </tbody> </table> </div> <h2 id="See_also">See also</h2> <ul> <li><a href="/en-US/docs/Web/Guide/HTML/HTML5/Constraint_validation">Form validation.</a></li> </ul>