为什么窗口仍然在此严格模式代码中定义？ [英] Why is window still defined in this strict mode code?

问题描述

"use strict";

setTimeout(function() {"use strict";console.log(this)}, 1000);

setTimeout调用的函数内部的'this'应该引用全局对象，但我也有使用严格;在身体里。然而它记录了窗口而不是未定义，这正是我所期待的。这里发生了什么？

The 'this' inside functions called by setTimeout should refer to global object, but I also have "use strict"; in the body. Yet it logs window instead of undefined, which is what I was expecting. What's happening here?

推荐答案

setTimeout 被定义为调用它在上下文中传递的函数window 。

实现运行算法的方法的对象（Window或WorkerGlobalScope object）作为方法上下文，

the object on which the method for which the algorithm is running is implemented (a Window or WorkerGlobalScope object) as the method context,

它类似于调用 yourfunction.apply（window）不是 yourfunction（）。

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