使用Javascript：困惑如何嵌套的for循环工作 [英] Javascript: confused about how nested for loops work

问题描述

为什么嵌套的 for循环的工作方式，他们在下面的例子做：

Why do nested for loops work in the way that they do in the following example:

var times = [
            ["04/11/10", "86kg"], 
            ["05/12/11", "90kg"],
            ["06/12/11", "89kg"]
];

for (var i = 0; i < times.length; i++) {
        var newTimes = [];
        for(var x = 0; x < times[i].length; x++) {
            newTimes.push(times[i][x]);
            console.log(newTimes);  


        }

    }

在这个例子中我想到的console.log会给我下面的输出：

In this example I would have thought console.log would give me the following output:

["04/11/10"]
["86kg"]
["05/12/11"]
["90kg"]
["06/12/11"]
["89kg"]

不过，我居然得到这样的：

However, I actually get this:

["04/11/10"]
["04/11/10", "86kg"]
["05/12/11"]
["05/12/11", "90kg"]
["06/12/11"]
["06/12/11", "89kg"]

有没有人能帮助我理解这一点？

Is anyone able to help me understand this?

编辑：

感谢您的答复！

推荐答案

您正在重新定义新时代上的每一个循环，你输出对每列推控制台。

You are redefining newTimes on every single loop and you are outputting to the console on each column push.

var times = [
            ["04/11/10", "86kg"], 
            ["05/12/11", "90kg"],
            ["06/12/11", "89kg"]
];
 var newTimes = [];
for (var i = 0; i < times.length; i++) {     
        for(var x = 0; x < times[i].length; x++) {
            newTimes.push(times[i][x]);
        }
    }
    console.log(newTimes);  

返回： [04/11/10，86公斤，11年5月12日，90公斤，06/12/11，89公斤]
http://jsfiddle.net/niklasvh/SuEdt/

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