在 javascript 原型事件处理程序中保留“this"引用 [英] Preserve 'this' reference in javascript prototype event handler

问题描述

在存储在对象原型内的事件处理程序中保留 this javascript 引用的正确方法是什么?我想远离创建像_this"或that"这样的临时变量，而且我不能使用像 jQuery 这样的框架.我看到很多人谈论使用绑定"功能，但不确定如何在我给定的场景中实现它.

What is the correct way to preserve a this javascript reference in an event handler stored inside the object's prototype? I'd like to stay away from creating temp vars like '_this' or 'that' and I can't use a framework like jQuery. I saw a lot of people talk about using a 'bind' function but was unsure of how to implement it in my given scenario.

var Example = function(foo,bar){
    this.foo = foo;
    this.bar = bar;
};
Example.prototype.SetEvent = function(){
    this.bar.onclick = this.ClickEvent;
};
Example.prototype.ClickEvent = function(){
    console.log(this.foo); // logs undefined because 'this' is really 'this.bar'
};

推荐答案

我发现 bind() 是迄今为止最干净的解决方案:

I find bind() being the cleanest solution so far:

this.bar.onclick = this.ClickEvent.bind(this);

顺便说一句，other this 通常被称为 that.

BTW the other this is called that by convention very often.

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