继承的编码实现

　　// 父类
    function Parent() {this.eyes = ‘blue‘}
    Parent.prototype.getEyes = function getEyes() {
        console.log(this.eyes)
    }

    // 子类
    function Chilren() {}

    // 原型链实现类的继承
    function extend(Chilren, Parent) {
        // 避免子类父类引用变量共享问题-引入临时新的构造函数
        function tem(){}
        tem.prototype = Parent.prototype

        Chilren.prototype = new Parent()
        Chilren.prototype.constructor = Chilren
    }

    // 验证
    extend(Chilren, Parent)
    let chilren = new Chilren()
    chilren.getEyes()