js原型继承理解

原型继承的3种实现

1 利用call实现冒充对象继承，继承了模板的属性和方法，未继承原型属性和方法

function Person(name, age) {
    this.name = name
    this.age = age
}

function Student1(name,age,sex) {
    Person.apply(this, arguments) 
    this.sex = sex
}
var s1 = new Student1('lili', 1, 'man')
console.log(s1)

2 利用prototype实现继承，缺点无法向父类传参

function Person(name, age) {
    this.name = name
    this.age = age
}

function Student2(sex) {
    this.sex = sex
}
Student2.prototype = new Person('xiaoming', 2)
Student2.prototype.constructor = Student2

var s2 = new Student2('women')
console.log(s2.name, s2.sex, s2.constructor)

3 混合继承

function Person(name, age) {
    this.name = name
    this.age = age
}
Person.prototype.hello = function (){
    console.log('world')
}
function Student3(name,age,sex) {
    Person.call(this,...arguments)
    this.sex = sex
}
Student3.prototype.__proto__ = Person.prototype
var s3 = new Student3('ming',3,'man')
console.log(s3.name,s3.sex,s3.hello,s3.constructor)