如何在请求调用时将值传递给回调函数？ [英] How to pass values to a callback function at the time of the request call?

问题描述

我有以下情况：

var foo = [ 0, 1, 2 ]
for (var i in foo) {
    Asyncstuff.get(URI).on('response', function(res) { console.log(i); } });
}

因为.on（'response'，...）被调用以异步方式，输出很可能是

Because the .on('response',...) is called in an asynchronous manner, the output will most likely be

2
2
2

在.get（）是否有可能传递 i 的值调用回调函数？

Is there a possibility to pass the value of i at the time the .get() is called to the callback function?

推荐答案

你需要一个闭包。有比这更好的方法，但这应该清楚地证明这个概念：

You need a closure. There are better ways than this, but this should clearly demonstrate the concept:

var foo = [ 0, 1, 2 ]
for (var i in foo) {
    (function(i){
        Asyncstuff.get(URI).on('response', function(res) { console.log(i); } });
    })(i);
}

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