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JavaScript prototype Property

❮ Complete Math Object Reference

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>

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
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❮ Complete Math Object Reference