Nodejs EventEmitter - 定义侦听器函数的范围 [英] Nodejs EventEmitter - Define scope for listener function

问题描述

我想要这样的工作：

var Events=require('events'),
    test=new Events.EventEmitter,
    scope={
        prop:true
    };

test.on('event',function() {
   console.log(this.prop===true);//would log true
});
test.emit.call(scope,'event');

但是，不幸的是，听众甚至没有被调用。有没有办法做这个W / EventEmitter？我可以 Function.bind 给听众，但是，我真的希望 EventEmitter 有一些特别的（或明显的; ）方法这样做...

But, unfortunately, the listener doesn't even get called. Is there any way to do this w/ EventEmitter? I could Function.bind to the listener, but, I'm really hoping EventEmitter has some special (or obvious ;) way to do this...

感谢您的帮助！

推荐答案

不，因为侦听器中的此值是事件发射器对象。

No, because the this value in the listener is the event emitter object.

但是你能做什么这是吗

var scope = {
  ...
};
scope._events = test._events;
test.emit.call(scope, ...);

您的事件处理程序未被调用的原因是因为所有处理程序都存储在<$ c $中c> ._ events 所以如果你复制 ._ events 就可以了。

The reason your event handler did not get called is because all the handlers are stored in ._events so if you copy ._events over it should work.

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