即用构造函数定义对象的所有函数的属性，用原型方式定义对象的函数属性(方法)。
代码如下:
<script type="text/javascript">
    debugger;
    function Car(sColor, iDoors, iMpg) {
        this.color = sColor,
        this.doors = iDoors;
        this.mpg = iMpg;
        this.drivers = new Array("Mike", "Sue");
   }
   Car.prototype.showColor = function () {
        alert(this.color);
   };
   var Car1 = new Car("red", 4, 23);
   var Car2 = new Car("blue", 3, 25);    
   Car1.drivers.push("Matt");    
   alert(Car1.drivers);
   alert(Car2.drivers);    
</script>