1.原型链继承
1.创建父类对象
2.创建子类函数对象
3.将父类的实例对象赋值给子类的原型
4.将子类的原型属性的构造函数设置为 子类本身
function Person(name) { this.name = name; } Person.prototype.setName = function (name) { this.name = name; } function Student(name, age) { this.name = name; this.age = age; } Student.prototype = new Person(); Student.prototype.constructor = Student; Student.prototype.setAge = function (age) { this.age = age } log(new Student("西欧阿米",14)); log(new Person("你好")) log(new Student() instanceof Student) log(new Student() instanceof Person)
2.借用构造函数
function Person(name,age) { this.name=name this.age=age } function Student(name,age,price) { Person.call(this,name,age);//借用构造函数模式 this.price=price; } var p=new Student("哈哈",12,123000);
3.原型和构造函数组合模式
function Person(name,age) { this.name=name this.age=age } Person.prototype.setName=function (name) { this.name=name; } function Student(name,age,price) { Person.call(this,name,age);//借用构造函数模式 this.price=price; } //设置原型 Student.prototype=new Person(); //修复构造函数 Student.prototype.constructor=Student; var p=new Student("哈哈",12,123000);