js基础之继承的实现

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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../其他/jq.js"></script>
</head>

<body>
    <script>
        //混入式继承
        function Dog(name, color) {
            this.name = name;
            this.color = color;
        }
        Dog.prototype.eat = function(x) {
            console.log(this.name + "吃了" + x);
        }
        var ni = new Dog("陪陪", "黑色");
        ni.eat("屎");
        var ta = {};
        for (const key in ni) {
            if (ni.hasOwnProperty(key)) {
                ta[key] = ni[key];
            }
        }
        console.log(ta);
        //我们只拿到了属性，方法都没有啊，而且还只搞了一个，这也叫继承？？？？

        //这种继承还像那么回事儿！
        //即可以拿到方法，又可以拿到属性
        //这叫替换原型继承
        function Y1() {

        }
        var y1 = new Y1();
        Y1.prototype = Dog.prototype;
        Y1 = Dog.prototype.constructor;
        var huu = new Y1("mo", "mo");
        console.log(huu);
        huu.eat("mi");
        //混合式,也就是瞎搞，拿了一堆属性而已
        function Y2() {
            for (var key in ni) {
                if (ni.hasOwnProperty(key)) {
                    this[key] = ni[key];
                }
            }
        }
        var y2 = new Y2();
        console.log(y2);
        //借助构造函数，没啥用
        function Y3(name, color) {
            Dog.prototype.constructor.call(this, name, color);
        }
        var y3 = new Y3("mo", "ko"); //call借代码，不要个脸
        console.log(y3);
    </script>
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js基础之继承的实现

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