前端this相关

前端this相关：

<script>
    //示例一
    function func1() {
        console.log(this);  //this代指window
    }
    func1();
    //window.func1();


    //示例二
    function Func() {
        this.name = "jia";  //this代指obj
    }
    var obj = new Func();
    console.log(obj.name);  //jia


    //示例三
    function Func2() {
        this.name = "kaylee";
        this.show = function () {
            console.log(this);  //this代指obj2
        }
    }
    var obj2 = new Func2();
    obj2.show();


    //示例四
    var userInfo = {
        name: "jia",
        age: 18,
        show: function () {
            console.log(this);  //this代指userInfo
        }
    };
    userInfo.show();


    //示例五
    var userInfo2 = {
        name: "kaylee",
        age: 18,
        show: function () {
            console.log(this);  //this代指userInfo2
            (function () {
                console.log(this);  //this代指window
            })()
        }
    };
    userInfo2.show();


    //示例五可以写作：
    var userInfo3 = {
        name: "kaylee",
        age: 18,
        show: function () {
            console.log(this);  //this代指userInfo3
            inner();
        }
    };
    userInfo3.show();

    function inner() {
        console.log(this);  //this代指window
    }


    //示例六
    var userInfo4={
        name:"kaylee",
        age:18,
        show:function () {
            console.log(this);  //this代指userInfo4
            var that = this;
            (function () {
                console.log(that);  //that代指userInfo4
            })()
        }
    };
    userInfo4.show();
</script>

总结：

　　函数被 对象.函数 执行，那么函数中的this就是该对象