javascript的这个对象以我认为的方式引用新创建的对象 [英] does javascript's this object refer to newly created object in the way i think

问题描述

所以，当我们创建构造函数创建新对象新的关键字做3事情
我要解释它，但请纠正我，如果我错了我想确定我正确

So, when we create constructor function for creating new object the new keyword does 3 things I'am going to explain it but please correct me if I'am wrong i want to be sure I'am correct

首先我将创建一个构造函数

first i will create a constructor function

function ObjectCreate(){
    this.a = "a";
    this.b = "b";

    ObjectCreate.prototype.show = function(){
        alert(this.a+" "+this.b);
    }
}

obj1 = new ObjectCreate();

现在的第一个关键字是create new object并设置它的构造函数原型的secret链接，传递给构造函数，现在 this 可以引用它，请注意这个不是指obj1这一点，因为一旦构造函数完成创建对象，然后它返回新创建的对象到obj1变量。我问这个问题，因为有些人说 this 在这种情况下引用obj1对象。

now the first thing new keyword does is create new object and set its secret link to its constructor's prototype and pass it to the constructor function where now the this can refer to it and please note this does not refer to obj1 at this point because once constructor finished creating object only then it returns the newly created object to obj1 variable. i ask this question because some people say that this refer to the obj1 object in this case. so am i right here.

推荐答案

在此示例中，在构造函数调用期间， obj1 未定义。在 ObjectCreate 函数返回后，将值分配给 obj1 变量。

In this example, during constructor invocation, obj1 is undefined. Value is assigned to obj1 variable after ObjectCreate function returns.

您可以检查自己：

function ObjectCreate(){
    this.a = "a";
    this.b = "b";

    alert(obj1); // yields "undefined"
    ObjectCreate.prototype.show = function(){
        alert(this.a+" "+this.b);
    }
}

var obj1 = new ObjectCreate(); // note "var"

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