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---
title: Object.prototype.toString()
slug: Web/JavaScript/Reference/Global_Objects/Object/toString
translation_of: Web/JavaScript/Reference/Global_Objects/Object/toString
---
<div>{{JSRef}}</div>
<p><code><strong>toString() </strong>methodu verilen nesneyi String'e dönüştürür.</code></p>
<h2 id="Syntax">Syntax</h2>
<pre class="syntaxbox"><code><var>obj</var>.toString()</code></pre>
<h2 id="Açıklama">Açıklama</h2>
<p>Every object has a <code>toString()</code> method that is automatically called when the object is to be represented as a text value or when an object is referred to in a manner in which a string is expected. By default, the <code>toString()</code> method is inherited by every object descended from <code>Object</code>. If this method is not overridden in a custom object, <code>toString()</code> returns "[object <em>type</em>]", where <code><em>type</em></code> is the object type. The following code illustrates this:</p>
<pre class="brush: js">var o = new Object();
o.toString(); // returns [object Object]
</pre>
<div class="note">
<p><strong>Note:</strong> Starting in JavaScript 1.8.5 <code>toString()</code> called on {{jsxref("null")}} returns <code>[object <em>Null</em>]</code>, and {{jsxref("undefined")}} returns <code>[object <em>Undefined</em>]</code>, as defined in the 5th Edition of ECMAScript and a subsequent Errata. See {{anch("Using_toString_to_detect_object_type", "Using toString to detect object type")}}.</p>
</div>
<h2 id="Examples">Examples</h2>
<h3 id="Overriding_the_default_toString_method">Overriding the default <code>toString</code> method</h3>
<p>You can create a function to be called in place of the default <code>toString()</code> method. The <code>toString()</code> method takes no arguments and should return a string. The <code>toString()</code> method you create can be any value you want, but it will be most useful if it carries information about the object.</p>
<p>The following code defines the <code>Dog</code> object type and creates <code>theDog</code>, an object of type <code>Dog</code>:</p>
<pre class="brush: js">function Dog(name, breed, color, sex) {
this.name = name;
this.breed = breed;
this.color = color;
this.sex = sex;
}
theDog = new Dog('Gabby', 'Lab', 'chocolate', 'female');
</pre>
<p>If you call the <code>toString()</code> method on this custom object, it returns the default value inherited from {{jsxref("Object")}}:</p>
<pre class="brush: js">theDog.toString(); // returns [object Object]
</pre>
<p>The following code creates and assigns <code>dogToString()</code> to override the default <code>toString()</code> method. This function generates a string containing the name, breed, color, and sex of the object, in the form "<code>property = value;</code>".</p>
<pre class="brush: js">Dog.prototype.toString = function dogToString() {
var ret = 'Dog ' + this.name + ' is a ' + this.sex + ' ' + this.color + ' ' + this.breed;
return ret;
}
</pre>
<p>With the preceding code in place, any time <code>theDog</code> is used in a string context, JavaScript automatically calls the <code>dogToString()</code> function, which returns the following string:</p>
<pre class="brush: js">"Dog Gabby is a female chocolate Lab"
</pre>
<h3 id="Using_toString()_to_detect_object_class">Using <code>toString()</code> to detect object class</h3>
<p><code>toString()</code> can be used with every object and allows you to get its class. To use the <code>Object.prototype.toString()</code> with every object, you need to call {{jsxref("Function.prototype.call()")}} or {{jsxref("Function.prototype.apply()")}} on it, passing the object you want to inspect as the first parameter called <code>thisArg</code>.</p>
<pre class="brush: js">var toString = Object.prototype.toString;
toString.call(new Date); // [object Date]
toString.call(new String); // [object String]
toString.call(Math); // [object Math]
// Since JavaScript 1.8.5
toString.call(undefined); // [object Undefined]
toString.call(null); // [object Null]
</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('ES1')}}</td>
<td>{{Spec2('ES1')}}</td>
<td>Initial definition. Implemented in JavaScript 1.0.</td>
</tr>
<tr>
<td>{{SpecName('ES5.1', '#sec-15.2.4.2', 'Object.prototype.toString')}}</td>
<td>{{Spec2('ES5.1')}}</td>
<td>Call on {{jsxref("Global_Objects/null", "null")}} returns <code>[object <em>Null</em>]</code>, and {{jsxref("Global_Objects/undefined", "undefined")}} returns <code>[object <em>Undefined</em>]</code></td>
</tr>
<tr>
<td>{{SpecName('ES6', '#sec-object.prototype.tostring', 'Object.prototype.toString')}}</td>
<td>{{Spec2('ES6')}}</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>
</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>
</tbody>
</table>
</div>
<h2 id="See_also">See also</h2>
<ul>
<li>{{jsxref("Object.prototype.toSource()")}}</li>
<li>{{jsxref("Object.prototype.valueOf()")}}</li>
</ul>
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