JS 类继承

// super-class A
var A = function(name) {
    this.name = name || "A";
};
A.prototype.fuck = "Fuck";
A.prototype.you = "U";
A.prototype.fuckyou = function() {
    console.info(this.fuck + " " + this.you);
};
// sub-class B using call
var B = function(name) {
    A.call(this, name || "B");
};
// sub-class C using prototype-chain
var C = function(name) {};
C.prototype = new A();
var D = function(name) {
    A.call(this, name || "D");
};
// sub-class D using call and prototype-chain
D.prototype = new A();
var a = new A("AA"),
    b = new B("BB"),
    c = new C("CC"),
    d = new D("DD");
// print results
console.dir(a);
console.dir(b);
console.dir(c);
console.dir(d);
console.info("instanceof:", a instanceof A, b instanceof A, c instanceof A, d instanceof A);
console.info("hasOwnProperty(name):", a.hasOwnProperty("name"), b.hasOwnProperty("name"), c.hasOwnProperty("name"), d.hasOwnProperty("name"));