machinecat520
/
zj-Exercise


			
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    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>

        function Person(name, age, gender) {
            this.name = name;
            this.age = age;
            this.gender = gender;
        }
  
        //修改Person原型的toString
        Person.prototype.toString = function () {
            return "Person[name=" + this.name + ",age=" + this.age + ",gender=" + this.gender + "]";
        };
        //创建一个Person实例
        var per = new Person("孙悟空", 28, "男");
        var per2 = new Person("二师兄", 38, "男");
        // 当我们直接在页面中打印一个对象时，实际上是输出对象的toString()方法的返回值
        // 如果我们希望在输出对象时不输出[onject Object]，可以为对象添加一个toString()方法
        per.toString = function(){
            return "我是一个快乐的小Person";
        }
        per.toString = function(){
            return "Person[name="+this.name+",age="+this.age+",gender="+this.gender+"]";
        };

        var result = per.toString();
        // console.log("result="+result);
        console.log(per);
        console.log(per2);
        console.log(per.hasOwnProperty("toString"));//输出结果为false
        console.log(per.__proto__.hasOwnProperty("toString"));//输出结果为false
        console.log(per.__proto__.__proto__.hasOwnProperty("toString"));//输出结果为true


    </script>
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