Revision 973395 of Document.queryCommandSupported()

<div>{{ApiRef("DOM")}}</div>

<p>The <code><strong>Document.queryCommandSupported()</strong></code> method reports whether or not the specified editor command is supported by the browser.</p>

<h2 id="Syntax">Syntax</h2>

<pre class="syntaxbox">
<var>isSupported</var> = document.queryCommandSupported(<var>command</var>);
</pre>

<dl>
 <dt>
 <h3 id="Parameters">Parameters</h3>
 </dt>
 <dt><code>command</code></dt>
 <dd>The command for which to determine support.</dd>
</dl>

<h3 id="Return_value">Return value</h3>

<p>Returns a {{jsxref("Boolean")}} which is <code>true</code> if the command is supported and <code>false</code> if the command isn't<code>.</code></p>

<h2 id="Notes">Notes</h2>

<p>The <code>'paste'</code> command return <code>false</code> not only if the feature is unavailable, but also if the script calling it has insufficient privileges to perform the action <a href="#note1">[1]</a></p>

<h2 id="Example">Example</h2>

<pre class="brush:js">
var flg = document.queryCommandSupported("SelectAll");

if(flg) {
  // ...Do something
}
</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 Editing','#querycommandsupported()','querycommandsupported')}}</td>
   <td>{{Spec2('HTML Editing')}}</td>
   <td>Initial definition</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>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>17</td>
   <td>{{CompatGeckoDesktop("9.0")}}<sup>[1]</sup></td>
   <td>4.0</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Android</th>
   <th>Firefox Mobile (Gecko)</th>
   <th>IE Mobile</th>
   <th>Opera Mobile</th>
   <th>Safari Mobile</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatGeckoMobile("9.0")}}<sup>[1]</sup></td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

<p>[1] Before Firefox 41, for the command <code>'paste'</code> Firefox incorrectly returned <code>true</code> when the paste feature was available but the calling script had insufficient privileges to actually perform the action.</p>

<h2 id="See_also">See also</h2>

<ul>
 <li>{{domxref("Document.execCommand()")}}</li>
 <li>{{domxref("Document.queryCommandEnabled()")}}</li>
</ul>