javascript中的继承

来源：互联网发布：2016美国非农就业数据编辑：程序博客网时间：2024/05/14 23:03

最常见的三种继承方式：

1.构造函数继承

//构造函数继承     function People(name){//实例属性this.name = name}function Student(school){//实例属性this.school = school;People.call(this,'小明')   //构造函数继承}//实例方法People.prototype.show = function(){console.log('success show') }var stu = new Student('星星幼儿园')stu.name;    //小明stu.show() //报错

缺点：只能继承父类的实例属性和方法，不能继承原型属性和方法

2.原型继承

//原型继承   function People(name){//实例属性this.name = name}function Student(school){//实例属性this.school = school}//实例方法People.prototype.show = function(){console.log('success show')} Student.prototype = new People()       //原型继承 var stu = new Student('星星幼儿园')    //创建子类实例时，无法向父类构造函数传参，因此name为undefinedstu.name;    //undefinedstu.show() //success show

缺点：创建子类实例时，无法向父类构造函数传参

3.组合继承（构造函数继承和原型继承）

//组合继承function People(name){//实例属性this.name = name}function Student(school){//实例属性this.school = school;People.call(this,'小明')}//实例方法People.prototype.show = function(){console.log('success show') }Student.prototype = new People()var stu = new Student('星星幼儿园')stu.name;    //小明stu.show() //success show

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