//首先創建父類
function Person(name, age, address) {
this.name = name;
this.age = age;
this.address = address;
}
//創建子類
function Student(score) {
this.score = score;
//可以用call方法或者是apply方法調用函數的構造函數
//調用父類的構造函數，通過call方法調用Person類的構造函數。這樣就會在student中初始化Person對象，student也就有了Person的屬性的副本
Person.call(this,"zhangsan",22,"中國北京！");
}

var student = new Student(100);
alert(student.address + student.score + "分");