JavaScript prototype Property: String Object

Last update on August 19 2022 21:50:37 (UTC/GMT +8 hours)

Description

The prototype property is used to add new properties and methods to an object.

Version

Implemented in JavaScript 1.1

Syntax

myobj.prototype.name = value

myobj: The name of the constructor function object you want to change

name: The name of the property or method to be created.

value: The value initially assigned to the new property or method.

If you add a property to the prototype for an object, then all objects created with that object's constructor function will have that new property, even if the objects existed before you created the new property.

Example:

The following web document demonstrates how the prototype property can be used.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript String object - prototype property example</title>
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
function stringgreen()
{
return "<font color=green ><b>  " +this.toString() + "</b></font>";
}
//]]>
</script>
</head>
<body>
<h1 style="color: red">JavaScript Number object : prototype property</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
String.prototype.string_green = stringgreen
document.write("www.w3resource.com".string_green())
//]]>
</script>
</body>
</html>

View the example in the browser

Supported Browser

Internet Explorer 7	Firefox 3.6	Google Chrome 7	Safari 5.0.1	Opera 10
Yes	Yes	Yes	Yes	Yes

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