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<h1>JavaScript Create Your Own Objects</h1><a href="js_timing.asp"><img alt="previous" border="0" src="../images/btn_previous.gif" width="100" height="20" /></a>
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<p class="intro">Objects are useful to organize information.</p>
<hr />
<h2>Examples</h2>
<p><a target="_blank" href="tryit.asp@filename=tryjs_create_object1">Create a
direct instance of an object</a></p>
<p><a target="_blank" href="tryit.asp@filename=tryjs_create_object2">Create a
template for an object</a></p>
<hr />
<h2>JavaScript Objects</h2>
<p>Earlier in this tutorial we have seen that JavaScript has several built-in objects, like String, Date, Array, and more. In addition to these built-in objects, you can also create your
own.</p>
<p>An object is just a special kind of data, with a collection of properties and methods.</p>
<p>Let's illustrate with an example: A person is an object. Properties are the values associated with
the object. The persons'
properties include name, height, weight, age, skin tone, eye color, etc. All persons
have these properties, but the values of those properties will differ from
person to person. Objects also have methods. Methods are the actions that can be performed on
objects. The persons' methods could be eat(), sleep(), work(), play(), etc.</p>
<h3>Properties</h3>
<p>The syntax for accessing a property of an object is:</p>
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<pre>objName.propName</pre>
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<p>You can add properties to an object by simply giving it a value. Assume that
the personObj already exists - you can give it properties named firstname,
lastname, age, and eyecolor as follows:</p>
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<pre>personObj.firstname="John";
personObj.lastname="Doe";
personObj.age=30;
personObj.eyecolor="blue";</pre>
<pre>document.write(personObj.firstname);</pre>
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<p>The code above will generate the following output:</p>
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<pre>John</pre>
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<h3>Methods</h3>
<p>An object can also contain methods.</p>
<p>You can call a method with the following syntax:</p>
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<pre>objName.methodName()</pre>
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<p><b>Note:</b> Parameters required for the method can be passed between the
parentheses.</p>
<p>To call a method called sleep() for the personObj:</p>
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<pre>personObj.sleep();</pre>
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<hr />
<h2>Creating Your Own Objects</h2>
<p>There are different ways to create a new object:</p>
<p><b>1. Create a direct instance of an object</b></p>
<p>The following code creates an instance of an object and adds four properties
to it:</p>
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<pre>personObj=new Object();
personObj.firstname="John";
personObj.lastname="Doe";
personObj.age=50;
personObj.eyecolor="blue";</pre>
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<p>Adding a method to the personObj is also simple. The following code adds a
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