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---
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>
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