运行程序,解读this指向---case3

片段1

var myObj = {
    fullname: "Hou Yi",
    getFullName: function(){
        var self = this;
        console.log('outer:this.fullname is ' + this.fullname);//this.fullname is Hou Yi
        console.log('outer:self.fullname is ' + self.fullname);//self.fullname is Hou Yi
        (function(){
            // 自执行函数的this一般情况下都指向window
            console.log('inner:this.fullname is ' + this.fullname);//this.fullname is undefined
            console.log('inner:self.fullname is ' + self.fullname);//self.fullname is Hou Yi
        })();
    }
};
myObj.getFullName();

片段2

//闭包
var fullname = "Camille Hou";
var myObj = {
    fullname:"Hou Yi",
    getFullName:function(){
        return function(){
            return this.fullname;
        }
    }
}
console.log(myObj.getFullName()());//Camille Hou
var fullname = "Camille Hou";
var myObj = {
    fullname:"Hou Yi",
    getFullName:function(){
        var that = this;
        return function(){
            return that.fullname;
        }
    }
}
console.log(myObj.getFullName()());//Hou Yi

片段3

var fullname = "Camille Hou";
var myObj = {
    fullname:"Hou Yi",
    getFullNameP:{
        fullname:"Gamiye",
        getFullName:function(){
            return this.fullname;
        }
    }
};
//this指向myObj.getFullNameP
/*
如果函数,被某一个对象所拥有,那么该函数在调用时,内部的this指向该对象。
*/
console.log(myObj.getFullNameP.getFullName());//Gamiye

var getName = myObj.getFullNameP.getFullName;
// this指向window,getName被隐式的作为全局对象的属性。
/*
如果函数独立调用,那么该函数在调用时,内部的this指向undefined。但是在非严格模式中,当this指向undefined时,它会被自动指向全局对象。
*/
console.log(getName());//Camille Hou

严格模式

'use strict'
var fullname = "Camille Hou";
var myObj = {
    fullname:"Hou Yi",
    getFullNameP:{
        fullname:"Gamiye",
        getFullName:function(){
            return this.fullname;
        }
    }
};

var getName = myObj.getFullNameP.getFullName;
console.log(getName());//Cannot read property 'fullname' of undefined,此时的this指向undefined
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