path: root/files/tr/web/javascript/reference/global_objects/function/apply/index.html

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

<p><code><strong>apply()</strong></code> methodu ile verilen bir "this" değeri ve diziyi(ya da dizi benzeri bir nesneyi) kullanarak bağımsız değişkenlerle bir işlevi(function) çağırır.</p>

<div class="note">
<p><strong>Not:</strong> <strong>call() , apply() </strong>syntaxları sizin de dikkat ettiğiniz gibi aynıdır. farkları şudur: <strong>call() </strong>: bir argüman listesini argüman olarak alırken, <strong>apply() </strong>argümanlardan oluşmuş bir array'ı argüman olarak kabul alır.  </p>
</div>

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

<pre class="syntaxbox"><var>fun</var>.apply(<var>thisArg, </var>[<var>argsArray</var>])</pre>

<h3 id="Parametreler">Parametreler</h3>

<dl>
 <dt><code>thisArg</code></dt>
 <dd>fun' ı çağırmak için atanan this in değeridir. Unutmayın, this,method tarafından görülen gerçek değer olmayabilir.: eğer method{{jsxref("Strict_mode", "non-strict mode", "", 1)}} içindeki bir kod ise{{jsxref("null")}}ve {{jsxref("undefined")}}global object ile yer değiştirecek, ve ilk değerleri saklanacak.</dd>
 <dt><code>argsArray</code></dt>
 <dd>
 <p>Eğer fonkiyona hiç bir parametre verilmeyecekse dizi benzeri bir nesne (çağrılacak fun'ın argümanlarını belirler), veya {{jsxref("null")}} veya {{jsxref("undefined")}}. ECMAScript 5 ile, bu argümanlar dizi yerine eşdeğer dizi benzeri nesne olabilir. {{anch("Browser_compatibility", "browser compatibility")}} için aşağıya bakın.</p>
 </dd>
</dl>

<h3 id="Dönen_değer">Dönen değer</h3>

<p><strong><code>this</code></strong> değeri ve argümanlar ile çağrılan fonksiyonun sonucu.</p>

<h2 id="Açıklama">Açıklama</h2>

<p>Varolan bir fonksiyonu çağırdığınızda farklı bir <strong>this</strong> objesi atayabilirsiniz. Burada <strong>this</strong> geçerli nesneyi (çağıran objeyi ) ifade eder. <strong>Apply</strong> ile bir kez yazılmış bir methodu  başka bir objeden miras alarak aynı fonksiyonu tekrar yazmaktan kurtulmuş  olursunuz.  </p>

<p><code>apply</code> is very similar to {{jsxref("Function.call", "call()")}}, except for the type of arguments it supports. You can use an arguments array instead of a named set of parameters. With <code>apply</code>, you can use an array literal, for example, <code><em>fun</em>.apply(this, ['eat', 'bananas'])</code>, or an {{jsxref("Array")}} object, for example, <code><em>fun</em>.apply(this, new Array('eat', 'bananas'))</code>.</p>

<p>You can also use {{jsxref("Functions/arguments", "arguments")}} for the <code>argsArray</code> parameter. <code>arguments</code> is a local variable of a function. It can be used for all unspecified arguments of the called object. Thus, you do not have to know the arguments of the called object when you use the <code>apply</code> method. You can use <code>arguments</code> to pass all the arguments to the called object. The called object is then responsible for handling the arguments.</p>

<p>Since ECMAScript 5th Edition you can also use any kind of object which is array-like, so in practice this means it's going to have a property <code>length</code> and integer properties in the range <code>(0...length-1)</code>. As an example you can now use a {{domxref("NodeList")}} or a custom object like <code>{ 'length': 2, '0': 'eat', '1': 'bananas' }</code>.</p>

<div class="note">
<p>Most browsers, including Chrome 14 and Internet Explorer 9, still do not accept array-like objects and will throw an exception.</p>
</div>

<h2 id="Examples">Examples</h2>

<h3 id="Using_apply_to_chain_constructors">Using <code>apply</code> to chain constructors</h3>

<p>You can use <code>apply</code> to chain {{jsxref("Operators/new", "constructors", "", 1)}} for an object, similar to Java. In the following example we will create a global {{jsxref("Function")}} method called <code>construct</code>, which will enable you to use an array-like object with a constructor instead of an arguments list.</p>

<pre class="brush: js">Function.prototype.construct = function (aArgs) {
  var oNew = Object.create(this.prototype);
  this.apply(oNew, aArgs);
  return oNew;
};
</pre>

<div class="note">
<p><strong>Note:</strong> The <code>Object.create()</code> method used above is relatively new. For an alternative method using closures, please consider the following alternative:</p>

<pre class="brush: js">Function.prototype.construct = function(aArgs) {
  var fConstructor = this, fNewConstr = function() {
    fConstructor.apply(this, aArgs);
  };
  fNewConstr.prototype = fConstructor.prototype;
  return new fNewConstr();
};</pre>
</div>

<p>Example usage:</p>

<pre class="brush: js">function MyConstructor() {
  for (var nProp = 0; nProp &lt; arguments.length; nProp++) {
    this['property' + nProp] = arguments[nProp];
  }
}

var myArray = [4, 'Hello world!', false];
var myInstance = MyConstructor.construct(myArray);

console.log(myInstance.property1);                // logs 'Hello world!'
console.log(myInstance instanceof MyConstructor); // logs 'true'
console.log(myInstance.constructor);              // logs 'MyConstructor'
</pre>

<div class="note">
<p><strong>Note:</strong> This non-native <code>Function.construct</code> method will not work with some native constructors (like {{jsxref("Date")}}, for example). In these cases you have to use the {{jsxref("Function.prototype.bind")}} method (for example, imagine having an array like the following, to be used with {{jsxref("Global_Objects/Date", "Date")}} constructor: <code>[2012, 11, 4]</code>; in this case you have to write something like: <code>new (Function.prototype.bind.apply(Date, [null].concat([2012, 11, 4])))()</code> — anyhow this is not the best way to do things and probably should not be used in any production environment).</p>
</div>

<h3 id="Using_apply_and_built-in_functions">Using <code>apply</code> and built-in functions</h3>

<p>Clever usage of <code>apply</code> allows you to use built-ins functions for some tasks that otherwise probably would have been written by looping over the array values. As an example here we are going to use <code>Math.max</code>/<code>Math.min</code> to find out the maximum/minimum value in an array.</p>

<pre class="brush: js">// min/max number in an array
var numbers = [5, 6, 2, 3, 7];

// using Math.min/Math.max apply
var max = Math.max.apply(null, numbers);
// This about equal to Math.max(numbers[0], ...)
// or Math.max(5, 6, ...)

var min = Math.min.apply(null, numbers);

// vs. simple loop based algorithm
max = -Infinity, min = +Infinity;

for (var i = 0; i &lt; numbers.length; i++) {
  if (numbers[i] &gt; max) {
    max = numbers[i];
  }
  if (numbers[i] &lt; min) {
    min = numbers[i];
  }
}
</pre>

<p>But beware: in using <code>apply</code> this way, you run the risk of exceeding the JavaScript engine's argument length limit. The consequences of applying a function with too many arguments (think more than tens of thousands of arguments) vary across engines (JavaScriptCore has hard-coded <a class="link-https" href="https://bugs.webkit.org/show_bug.cgi?id=80797">argument limit of 65536</a>), because the limit (indeed even the nature of any excessively-large-stack behavior) is unspecified. Some engines will throw an exception. More perniciously, others will arbitrarily limit the number of arguments actually passed to the applied function. (To illustrate this latter case: if such an engine had a limit of four arguments [actual limits are of course significantly higher], it would be as if the arguments <code>5, 6, 2, 3</code> had been passed to <code>apply</code> in the examples above, rather than the full array.) If your value array might grow into the tens of thousands, use a hybrid strategy: apply your function to chunks of the array at a time:</p>

<pre class="brush: js">function minOfArray(arr) {
  var min = Infinity;
  var QUANTUM = 32768;

  for (var i = 0, len = arr.length; i &lt; len; i += QUANTUM) {
    var submin = Math.min.apply(null,
                                arr.slice(i, Math.min(i+QUANTUM, len)));
    min = Math.min(submin, min);
  }

  return min;
}

var min = minOfArray([5, 6, 2, 3, 7]);
</pre>

<h3 id="Using_apply_in_monkey-patching">Using apply in "monkey-patching"</h3>

<p>Apply can be the best way to monkey-patch a built-in function of Firefox, or JS libraries. Given <code>someobject.foo</code> function, you can modify the function in a somewhat hacky way, like so:</p>

<pre class="brush: js">var originalfoo = someobject.foo;
someobject.foo = function() {
  // Do stuff before calling function
  console.log(arguments);
  // Call the function as it would have been called normally:
  originalfoo.apply(this, arguments);
  // Run stuff after, here.
}
</pre>

<p>This method is especially handy where you want to debug events, or interface with something that has no API like the various <code>.on([event]...</code> events, such as those usable on the <a href="/en-US/docs/Tools/Page_Inspector#Developer_API">Devtools Inspector</a>).</p>

<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('ES3')}}</td>
   <td>{{Spec2('ES3')}}</td>
   <td>Initial definition. Implemented in JavaScript 1.3.</td>
  </tr>
  <tr>
   <td>{{SpecName('ES5.1', '#sec-15.3.4.3', 'Function.prototype.apply')}}</td>
   <td>{{Spec2('ES5.1')}}</td>
   <td> </td>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#sec-function.prototype.apply', 'Function.prototype.apply')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td> </td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-function.prototype.apply', 'Function.prototype.apply')}}</td>
   <td>{{Spec2('ESDraft')}}</td>
   <td> </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>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
  </tr>
  <tr>
   <td>ES 5.1 generic array-like object as {{jsxref("Functions/arguments", "arguments")}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatGeckoDesktop("2.0")}}</td>
   <td>{{CompatUnknown}}</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>Chrome for 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>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
  </tr>
  <tr>
   <td>ES 5.1 generic array-like object as {{jsxref("Functions/arguments", "arguments")}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatGeckoMobile("2.0")}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

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

<ul>
 <li>{{jsxref("Functions/arguments", "arguments")}} object</li>
 <li>{{jsxref("Function.prototype.bind()")}}</li>
 <li>{{jsxref("Function.prototype.call()")}}</li>
 <li>{{jsxref("Functions", "Functions and function scope", "", 1)}}</li>
 <li>{{jsxref("Reflect.apply()")}}</li>
</ul>