javascipt 实现继承

//使用 call /apply实现继承,此方法针对父类中所有方法都不是以原型的方式实现的
function person(name,age){
this.name=name;
this.age=age;

this.show = function(){
console.log("call person   name:"+this.name+" age:"+this.age);
}
}

function student(name,age,grade){
person.call(this,name,age);

this.grade = grade;
}

student.prototype.showGrade = function(){
console.log("student call: grade:"+this.grade);
};

var stu = new student("zjw",24,1);
stu.show();
stu.showGrade();

//使用对象冒充实现继承
function person(name,age){
this.name=name;
this.age=age;

this.show = function(){
console.log("call person   name:"+this.name+" age:"+this.age);
}
}

function student(name,age,grade){
this.person=person;
this.person(name,age);
delete  this.person;

this.grade=grade;

this.showGrade = function(){
console.log("student call: grade:"+this.grade);
}
}

var stu = new student("zjw",24,1);
stu.show();
stu.showGrade();

//使用原型拷贝实现继承,这是最好的方式

function person(name,age){
this.name=name;
this.age = age;

this.show1 = function(){
console.log("person show1 call: name:"+this.name+" age:"+this.age);
}
}

person.prototype.show2 = function(){
console.log("person show2 call: name:"+this.name+" age:"+this.age);
};

function student(name,age,grade){

person.call(this,name,age);//拷贝name age show1

var prop;
//复制父类的以原型实现的方法
for (prop in person.prototype) {
var proto = this.constructor.prototype;

if (!proto[prop]) {
proto[prop] = person.prototype[prop];
}

proto[prop]["super"] = person.prototype;
}

this.grade=grade;
}

student.prototype.show = function(){
console.log("student show call: name:"+this.name+" age:"+this.age+" grade:"+this.grade);
};

var stu = new student("zjw",24,1);
stu.show1();
stu.show2();
stu.show();

function person(name,age,obj){

console.log("person call"+arguments.length);
this.name = name;
this.age = age;

this.obj = obj;

this.method1 = function(){
console.log("method1 call:"+this.name+"--"+this.age+"---"+this.obj);
}
}

person.prototype.method2 = function(){
console.log("method2 call："+this.name+"---"+this.age+"---"+this.obj);
};

function student(name,age,grade,obj){
person.call(this,name,age,obj);

}

function inherits(curClass,parentClass){
curClass.prototype = new parentClass();
}

inherits(student,person);

var stu1 = new student("zjw",24,1,[1,2,3]);
stu1.method1();
stu1.method2();