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<title>JavaScript Objects Introduction</title>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
<h1>JavaScript Objects Introduction</h1>
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<p class="intro">JavaScript is an Object Oriented Programming (OOP) language.
</p>
<p class="intro">An OOP language allows you to define your own objects and make your own variable types.</p>
<hr />
<h2>Object Oriented Programming</h2>
<p>JavaScript is an Object Oriented Programming (OOP) language.
An OOP language allows you to define your own objects and make your own variable types.</p>
<p>However, creating your own objects will be explained later, in the Advanced
JavaScript section. We will start by looking at the built-in
JavaScript objects, and how they are used. The next pages will explain each
built-in JavaScript object in detail.</p>
<p>Note that an object is just a special kind of data. An object has properties and methods.</p>
<hr />
<h2>Properties</h2>
<p>Properties are the values associated with an object.</p>
<p>In the following example we are using the length property of the String
object to return the
number of characters in a string:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table4">
<tr>
<td>
<pre><script type="text/javascript"></pre>
<pre>var txt="Hello World!";
document.write(txt.length);</pre>
<pre></script></pre>
</td>
</tr>
</table>
<p>The output of the code above will be:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table5">
<tr>
<td>
<pre>12</pre>
</td>
</tr>
</table>
<br />
<hr />
<h2>Methods</h2>
<p>Methods are the actions that can be performed on
objects.</p>
<p>In the following example we are using the toUpperCase() method of the String
object to display a
text in uppercase letters:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table6">
<tr>
<td>
<pre><script type="text/javascript"></pre>
<pre>var str="Hello world!";
document.write(str.toUpperCase());</pre>
<pre></script></pre>
</td>
</tr>
</table>
<p>The output of the code above will be:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table7">
<tr>
<td>
<pre>HELLO WORLD!</pre>
</td>
</tr>
</table>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
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