js 继承--call方法

var Person = function (name)
    {
        this.name = name;
        this.ShowName = function()
        {
            alert(this.name);
        }
    };
    
    var Employee = function(name,salary)
    {
        this.salary = salary;
        Person.call(this,name);
    };
    Employee.prototype = new Person();  //建一个基类的对象作为子类原型的原型，这里很有意思    
    Employee.prototype.ShowMeTheMoney = function()  //给子类添构造函数的prototype添加方法
    {
        alert(this.name + " $" + this.salary);
    };
        
    var NbaEmployee = function(name,salary,age)
    {
        this.age = age;
        Employee.call(this,name,salary);
    };
    NbaEmployee.prototype = new Employee();
    NbaEmployee.prototype.ShowAge = function()
    {
        alert(this.age);
    };    
    
    var BillGates = new Person("Bill Gates");   //创建基类Person的BillGates对象
    var SteveJobs = new Employee("Steve Jobs", 1234);   //创建子类Employee的SteveJobs对象

    BillGates.ShowName();       //通过对象直接调用到prototype的方法
    SteveJobs.ShowName();       //通过子类对象直接调用基类prototype的方法，关注！
    SteveJobs.ShowMeTheMoney(); //通过子类对象直接调用子类prototype的方法

    var Kobe = new NbaEmployee("Kobe", "2000W",29);
    Kobe.ShowName();

    Kobe.ShowMeTheMoney();

    Kobe.ShowAge();