<html>
<head>
<title>Example</title>
</head>
<body>
<script type="text/javascript">
function ClassA() {
}
ClassA.prototype.color = "red";
ClassA.prototype.sayColor = function () {
alert(this.color);
};
function ClassB() {
ClassB.prototype = new ClassA();
ClassB.prototype.name = "";
ClassB.prototype.sayName = function () {
alert(this.name);
var objA = new ClassA();
var objB = new ClassB();
objA.color = "blue";
objB.color = "red";
objB.name = "John";
objA.sayColor();
objB.sayColor();
objB.sayName();
</script>
</body>
</html>