JavaScript的嵌套函数失去范围 [英] Javascript nested function losing scope

问题描述

有人可以解释的范围如下code的结合，请

Can someone explains the scope binding of the following code please

window.name = "window";

object = {
       name: "object",
       method: function() {
             nestedMethod: function() {
                   console.log(this.name);
             }
             nestedMethod();
       }
}

object.method();  // print 'window'

我想我的问题是更多关于这个 ...为什么这个失去范围，默认为全球范围内？尽我们创造将继续在全球范围内？匿名函数

I think my question is more about this...why is this losing the scope and default to the global scope ? do all the anonymous functions that we created will go on the global scope ?

推荐答案

当你调用一个函数，只需书写 FUNC（），此在函数内部将指向全局对象。你的情况，你写的：

Whenever you call a function, simply by writing func(), this inside the function will point to the global object. In your case you write:

nestedMethod();

所以这个在 nestedMethod 是窗口对象。您可以使用呼叫（或适用）手动定义上下文为你函数调用：

So this inside nestedMethod is the window object. You can use call (or apply) to manually define a context for you function call:

nestedMethod.call(this);

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