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// js中，为了解决继承问题。
//创建了Person类，然后需要创建Man和Woman两个继承类，继承类需要继承Person内的属性。解决这一需求。

/* 1. 原型链继承*/
/*

function Parent1() {
    this.name = 'parent1';
    this.play = [1, 2, 3]
}

function Child1() {
    this.type = 'child2';
}

console.dir(new Child1()); // 此时prototype是Function
Child1.prototype = new Parent1();
console.dir(new Child1()); // 此时是 Parent1

    // 潜在问题.修改了一个属性，会导致其他的属性同时变更。侧面证明:指针指向同一块内存，所以会同时被改变。
let s1 = new Child1();
let s2 = new Child1();
console.log(s1.play,s2.play) // 1,2,3,, 1,2,3,
s1.play.push(4)
console.log(s1.play,s2.play) //  1,2,3,4, 1,2,3,4

*/

/** 2. 构造函数继承，解决prototype共享问题 */

/*
function Parent1() {
    this.name = 'parent1';
}
console.log(Parent1.prototype);
Parent1.prototype.getName = function () {
    return this.name;
}

function Child1() {
    Parent1.call(this);
    this.type = 'child1';
}

let child1 = new Child1();
let child2 = new Child1();
child1.name = 888;
console.log(child1.name,child2.name);
console.log(child1) */

/** 3.组合继承，前两种组合 */

function Parent3 () {
    this.name = 'parent3';
    this.play = [1,2,3];
}

Parent3.prototype.getName = function () {
    return this.name
}

function Child3 () {
    Parent3.call(this)
    this.type = 'child3';
}
console.log(new Child3());
Child3.prototype = new Parent3();
// 此时，Child3.prototype.constructor = Parent3
console.log(new Child3());
Child3.prototype.constructor = Child3;
let s3 = new Child3();
let s4 = new Child3();
s3.play.push(4);

console.log(s3.play,s4.play);

console.log(s3.getName())
console.log(s4.getName())