yige.org 试一个

<html>
<head>
<title>Example</title>
</head>
<body>
<script type="text/javascript">
function ClassA(sColor) {
    this.color = sColor;
}

ClassA.prototype.sayColor = function () {
    alert(this.color);
};

function ClassB(sColor, sName) {
    ClassA.call(this, sColor);
    this.name = sName;
}

ClassB.prototype = new ClassA();

ClassB.prototype.sayName = function () {
    alert(this.name);
};


var objA = new ClassA("blue");
var objB = new ClassB("red", "John");
objA.sayColor();
objB.sayColor();
objB.sayName();

</script>
 
</body>
</html>

结果:

编辑上面的代码，点击查看结果。

yige.org - 试一个