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JavaScript prototype Property

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Definition and Usage

The prototype property allows you to add properties and methods to an object.

Syntax

object.prototype.name=value

Example

In this example we will show how to use the prototype property to add a property to an object:

<script type="text/javascript">

function employee(name,jobtitle,born)
{
this.name=name;
this.jobtitle=jobtitle;
this.born=born;
}

var fred=new employee("Fred Flintstone","Caveman",1970);
employee.prototype.salary=null;
fred.salary=20000;

document.write(fred.salary);

</script>

The output of the code above will be:

20000

Try it yourself »
Math Object Reference Complete Math Object Reference

From http://www.w3schools.com (Copyright Refsnes Data)