JavaScript继承(类式继承)

js_class_extend.js

//JavaScript 类式继承
//YUI2.9 YHAOO.lang.extend
function extend(Sub, Super) {
  var F = function(){};
  F.prototype = Super.prototype;
  Sub.prototype = new F();
  Sub.prototype.constructor = Sub;
}

function Person(name){
  this.name = name;
}

Person.prototype.showName = function(){
  console.log(this.name);
};

function Student(name, age){
  Person.call(this, name);
  this.age = age;
}

extend(Student, Person);

Student.prototype.showAge = function(){
  console.log(this.age);
};

var s = new Student();
s.showAge();