JavaScript undefined Property

Definition and Usage The undefined property indicates that a variable has not been assigned a value. Syntax undefined Example In t...

Definition and Usage

The undefined property indicates that a variable has not been assigned a value.

Syntax

undefined


Example

In this example we will test two variables to find out if one of them is undefined:

<script type="text/javascript">
var t1="";
var t2;
if (t1==undefined)
{
document.write("t1 is undefined");
}
if (t2==undefined)
{
document.write("t2 is undefined");
}
</script>

The output of the code above will be:

t2 is undefined
Name

ADO,131,ASP,3,C++,61,CORE JAVA,1,CSS,115,HTML,297,index,5,JAVASCRIPT,210,OS,47,PHP,65,SAD,53,SERVLETS,23,SOFTWARE ENGINEERING,245,SQL,71,TCP/IP,1,XHTML,9,XML,18,
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Best Online Tutorials | Source codes | Programming Languages: JavaScript undefined Property
JavaScript undefined Property
Best Online Tutorials | Source codes | Programming Languages
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true
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