1.1借用构造函数
1 ?function supertype(){ 2 ?????????????this.colors = ["red","blue","green"]; 3 ?????????} 4 ?????????function subtype(){ 5 ?????????????supertype.call(this); 6 ?????????} 7 ??????????8 ?????????var instance1 = new subtype(); 9 ?????????instance1.colors.push(‘black‘);10 ?????????console.log(instance1.colors); 11 ?????????var instance2 = new subtype();12 ?????????console.log(instance2.colors); 1.2.相对于原型链而言，借用构造函数有一个很大的优势，即可以在子类型构造函数中向超类型构造函 数传递参数。
1 function supertype(name){ 2 ?????????????this.name = name; 3 ?????????} 4 ?????????function subtype(){ 5 ?????????????supertype.call(this,"gaoxuerong"); 6 ?????????????this.age = 21; 7 ?????????} 8 ?????????var instance1 = new subtype(); ?????????9 ?????????console.log(instance1.name); ?????????10 ?????????console.log(instance1.age); 2.组合继承:指的是将原型链和借用构造函数的 技术组合到一块，从而发挥二者之长的一种继承模式。其背后的思路是使用原型链实现对原型属性和方 法的继承，而通过借用构造函数来实现对实例属性的继承。这样，既通过在原型上定义方法实现了函数 复用，又能够保证每个实例都有它自己的属性.
1 ?function supertype(name){ 2 ?????????????this.name = name; 3 ?????????????this.colors = [‘red‘,‘green‘,‘black‘]; 4 ?????????} 5 ?????????supertype.prototype.sayname = function(){ 6 ?????????????console.log(this.name) 7 ?????????} 8 ?????????function subtype(name,age){ 9 ?????????????supertype.call(this,name);10 ?????????????this.age = age;11 ?????????}12 ?????????subtype.prototype ?= ?new supertype();13 ?????????subtype.prototype.constructor ?= ??subtype;14 ?????????subtype.prototype.sayage ?= ?function(){15 ?????????????console.log(this.age);16 ?????????}17 ?????????var instance1 = new subtype(‘gaoxuerong‘,21);18 ?????????instance1.colors.push(‘green‘);19 ??????????console.log(instance1.colors); 20 ?????????console.log(instance1.sayname()); ?????????21 ?????????console.log(instance1.sayage()); 22 ??????????var instance2 = new subtype(‘gxr‘,22);23 ?????????console.log(instance2.colors); ?????????24 ??????????console.log(instance2.sayname()); ?????????25 ?????????console.log(instance2.sayage()); 3.原型式继承:
1 function object(o){ 2 ?????????????function F(){} 3 ?????????????F.prototype = o; 4 ?????????????return new F(); 5 ?????????} 6 ?????????var person = { 7 ?????????????name:‘gxr‘, 8 ?????????????friends:[‘1‘,‘2‘,‘3‘] 9 ?????????}10 ?????????var anotherperson = object(person);11 ?????????anotherperson.friends.push(‘4‘);12 ?????????console.log(anotherperson.name); 13 ?????????console.log(anotherperson.friends);14 ??????????var yetanotherperson = object(person);15 ?????????yetanotherperson.name = ‘g‘;16 ?????????yetanotherperson.friends.push(‘5‘);17 ?????????console.log(yetanotherperson.name);18 ?????????console.log(yetanotherperson.friends);4.寄生式继承
1 function object(o){ 2 ?????????????function F(){} 3 ?????????????F.prototype = o; 4 ?????????????return new F(); 5 ?????????} 6 ?????????function createanother(original){ 7 ?????????????var clone = object(original); 8 ?????????????clone.sayHi = function(){ 9 ?????????????????console.log(‘hi‘);10 ?????????????}11 ?????????????return clone;12 ?????????}13 ?????????var person = {14 ?????????????name:‘gxr‘,15 ?????????????friends:[‘1‘,‘2‘,‘3‘]16 ?????????}17 ?????????var anotherperson = createanother(person);18 ?????????anotherperson.sayHi();5.寄生组合式继承:所谓寄生组合式继承，即通过借用构造函数来继承属性，通过原型链的混成形式来继承方法。其背 后的基本思路是：不必为了指定子类型的原型而调用超类型的构造函数，我们所需要的无非就是超类型 原型的一个副本而已。本质上，就是使用寄生式继承来继承超类型的原型，然后再将结果指定给子类型 的原型。
1 function object(o){ 2 ?????????????function F(){} 3 ?????????????F.prototype = o; 4 ?????????????return new F(); 5 ?????????} 6 ?????????function inheritprototype(subtype,supertype){ 7 ?????????????var prototype = object(supertype.prototype); 8 ?????????????prototype.constructor = subtype; 9 ?????????????subtype.prototype = prototype;10 ?????????}11 ?????????function supertype(name){12 ?????????????this.name = name;13 ?????????????this.colors = [‘red‘,‘green‘,‘black‘];14 ?????????}15 ?????????supertype.prototype.sayname = function(){16 ?????????????console.log(this.name)17 ?????????}18 ?????????function subtype(name,age){19 ?????????????supertype.call(this,name);20 ?????????????this.age = age;21 ?????????}22 ?????????inheritprototype(subtype,supertype);23 ?????????subtype.prototype.sayage ?= ?function(){24 ?????????????console.log(this.age);25 ?????????}js的几种继承方式
原文地址：https://www.cnblogs.com/gaoxuerong123/p/8552222.html