1. 原型链继承
Child.prototype = new Parent();
1 function Parent (name, age) { 2 this.name = name; 3 this.age = age; 4 } 5 Parent.prototype.say = function(){ 6 console.log('hello, my name is ' + this.name); 7 }; 8 function Child() { 9 }10 Child.prototype = new Parent('pursue');11 var child1 = new Child();12 child1.say(); //hello, my name is pursue13 var child2 = new Child();14 console.log(child1.say === child2.say);//true15 console.log(child1.name === child2.name);//true
2. call(thisObj, param1, param2,...)
1 function Parent(username){ 2 this.username = username; 3 this.hello = function(){ 4 alert(this.username); 5 } 6 } 7 function Child(username,password){ 8 Parent.call(this,username); 9 this.password = password;10 this.world = function(){11 alert(this.password);12 }13 }14 var parent = new Parent("zhangsan");15 var child = new Child("lisi","123456");16 parent.hello();17 child.hello();18 child.world();3. apply(thisObj, [param1,param2,...])
1 function Parent(username){ 2 this.username = username; 3 this.hello = function(){ 4 alert(this.username); 5 } 6 } 7 function Child(username,password){ 8 Parent.apply(this,new Array(username)); 9 this.password = password;10 this.world = function(){11 alert(this.password);12 }13 }14 var parent = new Parent("zhangsan");15 var child = new Child("lisi","123456");16 parent.hello();17 child.hello();18 child.world();
4. 组合继承(call+原型链 / apply+原型链)
1 function Parent(hello){ 2 this.hello = hello; 3 } 4 Parent.prototype.sayHello = function(){ 5 alert(this.hello); 6 } 7 function Child(hello,world){ 8 Parent.call(this,hello);//利用 call 方法 将父类的属性继承过来 9 //Parent.apply(this,new Array(hello));//利用 apply 方法 将父类的属性继承过来10 this.world = world;//新增一些属性11 }12 Child.prototype = new Parent();//将父类的方法继承过来13 Child.prototype.sayWorld = function(){//新增一些方法14 alert(this.world);15 }16 var c = new Child("zhangsan","lisi");17 c.sayHello();18 c.sayWorld();
5.寄生组合继承，与4相似，只是将原型链换做了Object.create(Parent.prototype)
1 function Parent(hello){ 2 this.hello = hello; 3 } 4 Parent.prototype.sayHello = function(){ 5 alert(this.hello); 6 } 7 function Child(hello,world){ 8 Parent.call(this,hello);//利用 call 方法 将父类的属性继承过来 9 //Parent.apply(this,new Array(hello));//利用 apply 方法 将父类的属性继承过来10 this.world = world;//新增一些属性11 }12 Child.prototype = Object.create(Parent.prototype);//将父类的方法继承过来13 Child.prototype.sayWorld = function(){//新增一些方法14 alert(this.world);15 }16 var c = new Child("zhangsan","lisi");17 c.sayHello();18 c.sayWorld();
