path: root/files/tr/web/javascript/reference/global_objects/object/freeze/index.html

---
title: Object.freeze()
slug: Web/JavaScript/Reference/Global_Objects/Object/freeze
translation_of: Web/JavaScript/Reference/Global_Objects/Object/freeze
---
<div>{{JSRef}}</div>

<p><code><strong>Object.freeze()</strong></code> metodu bir objeyi <strong>dondurmak</strong> amaçlı kullanılır. Bir obje dondurulduktan sonra artık değiştirilemez, yeni bir property eklenemez, çıkarılamaz veya değiştirilemez. Objenin propertyleri üzerinde herhangi bir düzenleme veya konfigurasyon yapılamaz. Bir obje dondurulduktan sonra sadece property'lerini değil bu objeye bağlı olan prototype da değiştir. <code>freeze()</code> metodu kendisine verilen objeyi dondurulmuş olarak geri döndürür ancak gelen değişkenin yeniden atanması zorunlu değildir.  <code>freeze()</code> metoduna gönderdiğiniz obje referans yoluyla geçeceği için tekrardan bir atama işlemi yapmak zorunda değilsiniz. Redux dahil bir çok state yönetim sistemleri bu metodu kullanarak state objesini immutable - değiştirilemez - yapmakta ve bu işleme bağlı olarak store üzerinden gerçekleştirilen işlemleri yenilemektedir. </p>

<div>{{EmbedInteractiveExample("pages/js/object-freeze.html")}}</div>



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

<pre class="syntaxbox notranslate"><code>Object.freeze(<var>obje</var>)</code></pre>

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

<dl>
 <dt><code>obje</code></dt>
 <dd>Dondurmak istediğiniz obje.</dd>
</dl>

<h3 id="Dönüt">Dönüt</h3>

<p>Metoda gönderilen obje dondurularak geri döndürülür</p>

<h2 id="Description">Description</h2>

<p>Dondurulmuş obje üzerinde hiç bir düzenleme, ekleme ve çıkarma işlemi yapılamaz. Bu amaçla yapılan herhangi bir değişim {{jsxref("TypeError")}} hatası verir (Farklı çevrelerde daha alt seviye hatalar vermesine karşın, {{jsxref("Strict_mode", "strict mode", "", 1)}} etkinleştirildiği durumlarda  {{jsxref("TypeError")}} hatası kesin olarak alınır).</p>

<p>Dondurulmuş bir objeye ait değer değiştirilemez, <code>writeable</code> ve <code>configurable</code> özellikleri <code>false</code> olarka atanır. Accessor properties (getter and setter) work the same (and still give the illusion that you are changing the value). Note that values that are objects can still be modified, unless they are also frozen. As an object, an array can be frozen; after doing so, its elements cannot be altered and no elements can be added to or removed from the array.</p>

<p><code>freeze()</code> returns the same object that was passed into the function. It <em>does not</em> create a frozen copy.</p>

<p>In ES5, if the argument to this method is not an object (a primitive), then it will cause a {{jsxref("TypeError")}}. In ES2015, a non-object argument will be treated as if it were a frozen ordinary object, and be simply returned.</p>

<pre class="brush: js notranslate">&gt; Object.freeze(1)
TypeError: 1 is not an object // ES5 code

&gt; Object.freeze(1)
1                             // ES2015 code
</pre>

<p>An <a href="/en-US/docs/Web/API/ArrayBufferView" title="ArrayBufferView is a helper type representing any of the following JavaScript TypedArray types:"><code>ArrayBufferView</code></a> with elements will cause a {{jsxref("TypeError")}}, as they are views over memory and will definitely cause other possible issues:</p>

<pre class="brush: js notranslate">&gt; Object.freeze(new Uint8Array(0)) // No elements
Uint8Array []

&gt; Object.freeze(new Uint8Array(1)) // Has elements
TypeError: Cannot freeze array buffer views with elements

&gt; Object.freeze(new DataView(new ArrayBuffer(32))) // No elements
DataView {}

&gt; Object.freeze(new Float64Array(new ArrayBuffer(64), 63, 0)) // No elements
Float64Array []

&gt; Object.freeze(new Float64Array(new ArrayBuffer(64), 32, 2)) // Has elements
TypeError: Cannot freeze array buffer views with elements
</pre>

<p>Note that; as the standard three properties (<code>buf.byteLength</code>, <code>buf.byteOffset</code> and <code>buf.buffer</code>) are read-only (as are those of an {{jsxref("ArrayBuffer")}} or {{jsxref("SharedArrayBuffer")}}), there is no reason for attempting to freeze these properties.</p>

<h3 id="Comparison_to_Object.seal">Comparison to <code>Object.seal()</code></h3>

<p>Objects sealed with {{jsxref("Object.seal()")}} can have their existing properties changed. Existing properties in objects frozen with <code>Object.freeze()</code> are made immutable.</p>

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

<h3 id="Freezing_objects">Freezing objects</h3>

<pre class="brush: js notranslate">var obj = {
  prop: function() {},
  foo: 'bar'
};

// Before freezing: new properties may be added,
// and existing properties may be changed or removed
obj.foo = 'baz';
obj.lumpy = 'woof';
delete obj.prop;

// Freeze.
var o = Object.freeze(obj);

// The return value is just the same object we passed in.
o === obj; // true

// The object has become frozen.
Object.isFrozen(obj); // === true

// Now any changes will fail
obj.foo = 'quux'; // silently does nothing
// silently doesn't add the property
obj.quaxxor = 'the friendly duck';

// In strict mode such attempts will throw TypeErrors
function fail(){
  'use strict';
  obj.foo = 'sparky'; // throws a TypeError
  delete obj.foo; // throws a TypeError
  delete obj.quaxxor; // returns true since attribute 'quaxxor' was never added
  obj.sparky = 'arf'; // throws a TypeError
}

fail();

// Attempted changes through Object.defineProperty;
// both statements below throw a TypeError.
Object.defineProperty(obj, 'ohai', { value: 17 });
Object.defineProperty(obj, 'foo', { value: 'eit' });

// It's also impossible to change the prototype
// both statements below will throw a TypeError.
Object.setPrototypeOf(obj, { x: 20 })
obj.__proto__ = { x: 20 }
</pre>

<h3 id="Freezing_arrays">Freezing arrays</h3>

<pre class="brush: js notranslate">let a = [0];
Object.freeze(a); // The array cannot be modified now.

a[0] = 1; // fails silently

// In strict mode such attempt will throw a TypeError
function fail() {
  "use strict"
  a[0] = 1;
}

fail();

// Attempted to push
a.push(2); // throws a TypeError</pre>

<p>The object being frozen is <em>immutable</em>. However, it is not necessarily <em>constant</em>. The following example shows that a frozen object is not constant (freeze is shallow).</p>

<pre class="brush: js notranslate">obj1 = {
  internal: {}
};

Object.freeze(obj1);
obj1.internal.a = 'aValue';

obj1.internal.a // 'aValue'</pre>

<p>To be a constant object, the entire reference graph (direct and indirect references to other objects) must reference only immutable frozen objects. The object being frozen is said to be immutable because the entire object <em>state</em> (values and references to other objects) within the whole object is fixed. Note that strings, numbers, and booleans are always immutable and that Functions and Arrays are objects.</p>

<h4 id="What_is_shallow_freeze">What is "shallow freeze"?</h4>

<p>The result of calling <code>Object.freeze(<var>object</var>)</code> only applies to the immediate properties of <code>object</code> itself and will prevent future property addition, removal or value re-assignment operations <em>only</em> on <code>object</code>. If the value of those properties are objects themselves, those objects are not frozen and may be the target of property addition, removal or value re-assignment operations.</p>

<pre class="brush: js notranslate">var employee = {
  name: "Mayank",
  designation: "Developer",
  address: {
    street: "Rohini",
    city: "Delhi"
  }
};

Object.freeze(employee);

employee.name = "Dummy"; // fails silently in non-strict mode
employee.address.city = "Noida"; // attributes of child object can be modified

console.log(employee.address.city) // Output: "Noida"
</pre>

<p>To make an object immutable, recursively freeze each property which is of type object (deep freeze). Use the pattern on a case-by-case basis based on your design when you know the object contains no <a href="https://en.wikipedia.org/wiki/Cycle_(graph_theory)" title="cycles">cycles</a> in the reference graph, otherwise an endless loop will be triggered. An enhancement to <code>deepFreeze()</code> would be to have an internal function that receives a path (e.g. an Array) argument so you can suppress calling <code>deepFreeze()</code> recursively when an object is in the process of being made immutable. You still run a risk of freezing an object that shouldn't be frozen, such as [window].</p>

<pre class="brush: js notranslate">function deepFreeze(object) {

  // Retrieve the property names defined on object
  var propNames = Object.getOwnPropertyNames(object);

  // Freeze properties before freezing self

  for (let name of propNames) {
    let value = object[name];

    if(value &amp;&amp; typeof value === "object") {
      deepFreeze(value);
    }
  }

  return Object.freeze(object);
}

var obj2 = {
  internal: {
    a: null
  }
};

deepFreeze(obj2);

obj2.internal.a = 'anotherValue'; // fails silently in non-strict mode
obj2.internal.a; // null
</pre>

<h2 id="Specifications">Specifications</h2>

<table class="standard-table">
 <thead>
  <tr>
   <th scope="col">Specification</th>
  </tr>
 </thead>
 <tbody>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-object.freeze', 'Object.freeze')}}</td>
  </tr>
 </tbody>
</table>

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



<p>{{Compat("javascript.builtins.Object.freeze")}}</p>

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

<ul>
 <li>{{jsxref("Object.isFrozen()")}}</li>
 <li>{{jsxref("Object.preventExtensions()")}}</li>
 <li>{{jsxref("Object.isExtensible()")}}</li>
 <li>{{jsxref("Object.seal()")}}</li>
 <li>{{jsxref("Object.isSealed()")}}</li>
</ul>