SOURCE

// 父类
function Parent(name) {
    this.name = name;
}
Parent.prototype.sayName = function() {
    console.log("Parent name is " + this.name);
}

// 子类
function Child (name, parentName) {
    Parent.call(this, parentName);
    this.name = name;
}

// 继承方法
function create (parent) {
    function F() {};
    F.prototype = parent.prototype;
    return new F();
}

Child.prototype = create(Parent);
Child.prototype.sayName = function() {
	console.log('child name:', this.name)
}
Child.prototype.constructor = Child;
var parent = new Parent('father');
parent.sayName();
var child = new Child('son', 'father');