js对象的几种创建方法和for- in 遍历对象

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系统内置对象

var diannao = new Object();
        diannao.color = "red";
        diannao.zongliang = 20;
        diannao.pinapai = "msi";
        diannao.xinghao = "Ge60-448";
        diannao.kandianying = function () {
                console.log("看电影");
        };
        diannao.yinyu = function () {
                console.log("听音乐");
        };
        diannao.youxi = function () {
                console.log("打游戏");
        };
        diannao.daima = function () {
                console.log("敲代码");
        };

//打印结果到控制台
diannao.daima();
console.log(diannao.xinghao);

自定义构造函数对象

function dianNao() {
    var diannao1 = new Object;
    diannao1.color = "red";
        diannao1.zongliang = 20;
        diannao1.pinapai = "msi";
        diannao1.xinghao = "Ge60-448";
        diannao1.kandianying = function () {
                console.log("看电影");
        };
        diannao1.yinyu = function () {
                console.log("听音乐");
        };
        diannao1.youxi = function () {
                console.log("打游戏");
        };
        diannao1.daima = function () {
                console.log("敲代码");
        };

        return diannao1;
}

//打印结果到控制台
var diannao = new dianNao();
console.log(diannao.xinghao);

字面量对象

var diannao2 = {
        color : "red",
    zongliang : "20",
      pinapai : "msi",
      xinghao : "Ge60-448",
  kandianying : function () {
            console.log("看电影");
  },
        yinyu : function () {
            console.log("听音乐");
  },
        youxi : function () {
            console.log("打游戏");
  },
        daima : function () {
            console.log("敲代码");
  },
}

//打印结果到控制台
console.log(diannao2.color);
diannao2.yinyu();
console.log(diannao2["yinyu"]);

工厂模式

function dianNao() {
    this.color = "red";
    this.zongliang = 20;
    this.pinapai = "msi";
    this.xinghao = "Ge60-448";
    this.kandianying = function () {
                console.log("看电影");
        };
        this.yinyu = function () {
                console.log("听音乐");
        };
        this.youxi = function () {
                console.log("打游戏");
        };
        this.daima = function () {
                console.log("敲代码");
        };
}
var diannao = new dianNao();
console.log(diannao["color"]);
console.log(diannao.xinghao);

for - in 遍历对象

var arr = {
    "name" : "zhangshuai",
    "sex" : "nan",
    "age" : "18",
};

for(var key in arr ){
    console.log(key + "======" + arr["key"]);
}