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diff --git a/files/tr/web/javascript/reference/global_objects/promise/catch/index.html b/files/tr/web/javascript/reference/global_objects/promise/catch/index.html deleted file mode 100644 index 3360f87fbb..0000000000 --- a/files/tr/web/javascript/reference/global_objects/promise/catch/index.html +++ /dev/null @@ -1,201 +0,0 @@ ---- -title: Promise.prototype.catch() -slug: Web/JavaScript/Reference/Global_Objects/Promise/catch -tags: - - JavaScript - - Promise - - Prototype - - fonksiyon - - metod -translation_of: Web/JavaScript/Reference/Global_Objects/Promise/catch ---- -<div>{{JSRef}}</div> - -<p>The <strong>catch()</strong> method returns a <code>Promise</code> and deals with rejected cases only. It behaves the same as calling {{jsxref("Promise.then", "Promise.prototype.then(undefined, onRejected)")}} (in fact, calling <code>obj.catch(onRejected)</code> internally calls <code>obj.then(undefined, onRejected)</code>). This means, that you have to provide <code>onRejected</code> function even if you want to fallback to <code>undefined</code> result value - for example <code>obj.catch(() => {})</code>.</p> - -<div>{{EmbedInteractiveExample("pages/js/promise-catch.html")}}</div> - - - -<p class="hidden">The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone <a href="https://github.com/mdn/interactive-examples">https://github.com/mdn/interactive-examples</a> and send us a pull request.</p> - -<p class="hidden">The source for this interactive demo is stored in a GitHub repository. If you'd like to contribute to the interactive demo project, please clone <a href="https://github.com/mdn/interactive-examples">https://github.com/mdn/interactive-examples</a> and send us a pull request.</p> - -<h2 id="Sözdizimi">Sözdizimi</h2> - -<pre class="syntaxbox"><var>p.catch(onRejected)</var>; - -p.catch(function(reason) { - // rejection -}); -</pre> - -<h3 id="Parametreler">Parametreler</h3> - -<dl> - <dt>onRejected</dt> - <dd>A {{jsxref("Function")}} called when the <code>Promise</code> is rejected. This function has one argument: - <dl> - <dt><code>reason</code></dt> - <dd>The rejection reason.</dd> - </dl> - The Promise returned by <code>catch()</code> is rejected if <code>onRejected</code> throws an error or returns a Promise which is itself rejected; otherwise, it is resolved.</dd> -</dl> - -<h3 id="Dönen_değer">Dönen değer</h3> - -<p>Internally calls <code>Promise.prototype.then</code> on the object upon which is called, passing the parameters <code>undefined</code> and the <code>onRejected</code> handler received; then returns the value of that call (which is a {{jsxref("Promise")}}).</p> - -<div class="warning"> -<p>Note the examples below are throwing instances of <a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error">Error</a>. This is considered good practice in contrast to throwing Strings: Otherwise the part doing the catching would have to make checks to see if the argument was a string or an error, and you might lose valuable information like stack traces.</p> -</div> - -<p><strong>Demonstration of the internal call:</strong></p> - -<pre class="brush: js">// overriding original Promise.prototype.then/catch just to add some logs -(function(Promise){ - var originalThen = Promise.prototype.then; - var originalCatch = Promise.prototype.catch; - - Promise.prototype.then = function(){ - console.log('> > > > > > called .then on %o with arguments: %o', this, arguments); - return originalThen.apply(this, arguments); - }; - Promise.prototype.catch = function(){ - console.log('> > > > > > called .catch on %o with arguments: %o', this, arguments); - return originalCatch.apply(this, arguments); - }; - -})(this.Promise); - - - -// calling catch on an already resolved promise -Promise.resolve().catch(function XXX(){}); - -// logs: -// > > > > > > called .catch on Promise{} with arguments: Arguments{1} [0: function XXX()] -// > > > > > > called .then on Promise{} with arguments: Arguments{2} [0: undefined, 1: function XXX()] -</pre> - -<h2 id="Açıklama">Açıklama</h2> - -<p>The <code>catch</code> method can be useful for error handling in your promise composition.</p> - -<h2 id="Örnekler">Örnekler</h2> - -<h3 id="Using_and_chaining_the_catch_method">Using and chaining the <code>catch</code> method</h3> - -<pre class="brush: js">var p1 = new Promise(function(resolve, reject) { - resolve('Success'); -}); - -p1.then(function(value) { - console.log(value); // "Success!" - throw new Error('oh, no!'); -}).catch(function(e) { - console.log(e.message); // "oh, no!" -}).then(function(){ - console.log('after a catch the chain is restored'); -}, function () { - console.log('Not fired due to the catch'); -}); - -// The following behaves the same as above -p1.then(function(value) { - console.log(value); // "Success!" - return Promise.reject('oh, no!'); -}).catch(function(e) { - console.log(e); // "oh, no!" -}).then(function(){ - console.log('after a catch the chain is restored'); -}, function () { - console.log('Not fired due to the catch'); -}); -</pre> - -<h3 id="Gotchas_when_throwing_errors">Gotchas when throwing errors</h3> - -<pre class="brush: js">// Throwing an error will call the catch method most of the time -var p1 = new Promise(function(resolve, reject) { - throw new Error('Uh-oh!'); -}); - -p1.catch(function(e) { - console.log(e); // "Uh-oh!" -}); - -// Errors thrown inside asynchronous functions will act like uncaught errors -var p2 = new Promise(function(resolve, reject) { - setTimeout(function() { - throw new Error('Uncaught Exception!'); - }, 1000); -}); - -p2.catch(function(e) { - console.log(e); // This is never called -}); - -// Errors thrown after resolve is called will be silenced -var p3 = new Promise(function(resolve, reject) { - resolve(); - throw new Error('Silenced Exception!'); -}); - -p3.catch(function(e) { - console.log(e); // This is never called -});</pre> - -<h3 id="If_it_is_resolved">If it is resolved</h3> - -<pre class="brush: js">//Create a promise which would not call onReject -var p1 = Promise.resolve("calling next"); - -var p2 = p1.catch(function (reason) { - //This is never called - console.log("catch p1!"); - console.log(reason); -}); - -p2.then(function (value) { - console.log("next promise's onFulfilled"); /* next promise's onFulfilled */ - console.log(value); /* calling next */ -}, function (reason) { - console.log("next promise's onRejected"); - console.log(reason); -});</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('ES2015', '#sec-promise.prototype.catch', 'Promise.prototype.catch')}}</td> - <td>{{Spec2('ES2015')}}</td> - <td>Initial definition in an ECMA standard.</td> - </tr> - <tr> - <td>{{SpecName('ESDraft', '#sec-promise.prototype.catch', 'Promise.prototype.catch')}}</td> - <td>{{Spec2('ESDraft')}}</td> - <td> </td> - </tr> - </tbody> -</table> - -<h2 id="Tarayıcı_uyumluluğu">Tarayıcı uyumluluğu</h2> - -<p class="hidden">To contribute to this compatibility data, please write a pull request against this repository: <a href="https://github.com/mdn/browser-compat-data">https://github.com/mdn/browser-compat-data</a>.</p> - -<p>{{Compat("javascript.builtins.Promise.catch")}}</p> - -<h2 id="Ayrıca_bakınız">Ayrıca bakınız</h2> - -<ul> - <li>{{jsxref("Promise")}}</li> - <li>{{jsxref("Promise.prototype.then()")}}</li> -</ul> |