---
title: Promise.prototype.catch()
slug: Web/JavaScript/Reference/Global_Objects/Promise/catch
translation_of: Web/JavaScript/Reference/Global_Objects/Promise/catch
---
<div>{{JSRef}}</div>

<p>Il metodo <strong>catch()</strong> restituisce una <code>Promise</code> e si occusa esclusivamente nei casi respinti. Si comporta come una chiamata {{jsxref("Promise.then", "Promise.prototype.then(undefined, onRejected)")}}.</p>

<p> </p>

<h2 id="Sintassi">Sintassi</h2>

<pre class="syntaxbox"><var>p.catch(onRejected)</var>;

p.catch(function(reason) {
   // rejection
});
</pre>

<h3 id="Parametri">Parametri</h3>

<dl>
 <dt>onRejected</dt>
 <dd>Una {{jsxref("Function")}} chiamata quando la <code>Promise</code> viene respinta. Questa funzione richiede un parametro, la motivazione della respinta.</dd>
</dl>

<h2 id="Descrizione">Descrizione</h2>

<p>Il metodo <code>catch</code> può essere utile per gestire errori nella composizione delle promise.</p>

<h2 id="Esempi">Esempi</h2>

<h3 id="Uso_del_metodo_catch">Uso del metodo catch</h3>

<pre class="brush: js">var p1 = new Promise(function(resolve, reject) {
  resolve("Success");
});

p1.then(function(value) {
  console.log(value); // "Success!"
  throw "oh, no!";
}).catch(function(e) {
  console.log(e); // "oh, no!"
});
</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('ES6', '#sec-promise.prototype.catch', 'Promise.prototype.catch')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>Initial definition in an ECMA standard.</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>

<p>{{CompatibilityTable}}</p>

<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>32</td>
   <td>{{CompatGeckoDesktop(29.0)}} [1]</td>
   <td>{{CompatNo}}</td>
   <td>19</td>
   <td>7.1</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>
   <th>Chrome for Android</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatGeckoMobile(29.0)}} [1]</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
   <td>8</td>
   <td>32</td>
  </tr>
 </tbody>
</table>
</div>

<p>[1] Gecko 24 has an experimental implementation of <code>Promise</code>, under the initial name of <code>Future</code>. It got renamed to its final name in Gecko 25, but disabled by default behind the flag <code>dom.promise.enabled</code>. <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=918806">Bug 918806</a> enabled Promises by default in Gecko 29.</p>

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

<ul>
 <li>{{jsxref("Promise")}}</li>
 <li>{{jsxref("Promise.prototype.then()")}}</li>
</ul>