包含MooTools的for..in的Javascript数组迭代 [英] Javascript array iteration using for..in with MooTools included

问题描述

我在MooTools中迭代一个数组，但在使用简写 for..in 循环遍历数组时看到其他项目。当我使用常规的进行循环时，它工作正常。这是MooTools污染全局命名空间的问题还是我在这里做错了什么？

I am iterating over an array in MooTools but seeing additional items when iterating through the array using the shorthand for..in loop. It works fine when I use the regular for loop. Is this a problem with MooTools polluting the global namespace or am I doing something wrong here?

有一个 createTabs（）迭代数组并为数组中的每个值创建一个选项卡的函数：

There is a createTabs() function that iterates over an array and creates a tab for each value in the array:

function createTabs() {
    var myTabs = [["First", "a.png"], ["Second", "b.png"]];
    for(var i in myTabs) {
        var tab = new Tab(myTabs[i][0], myTabs[i][1]);
        console.log(i);
    }
}

这是的输出console.log（i）：

0
1
$family
each
clean
associate
link
contains
extend
getLast
getRandom
include
combine
erase
empty
flatten
hexToRgb
rgbToHex
toJSON

我理解前2个索引，但其余的来自哪里？

I understand the first 2 indexes, but where is the rest coming from?

编辑：谢谢快速回答Chetan和k Prime。这是有道理的，MooTools的 Array.each 添加是更清晰的迭代方式！

Edit: Thanks for the quick answers Chetan and k Prime. That makes sense, and the Array.each addition by MooTools is much cleaner way to iterate!

看起来很多现在更好：

myTabs.each(function(item) {
    var tab = new Tab(item[0], item[1]);
    console.log(item);
});

推荐答案

for..in 不适用于数组迭代。它迭代非内置对象的所有属性。由于MooTools为Array原型添加了更多功能，因此它们现在也是数组属性。请参阅此 https://developer.mozilla.org/En/Core_JavaScript_1 .5_Reference / Statements / For ... in

for..in is not meant for array iteration. It iterates over all the properties of an object that are not built-in. Since MooTools has added more functions to Array prototype, they are now array properties as well. See this https://developer.mozilla.org/En/Core_JavaScript_1.5_Reference/Statements/For...in

只需使用基本for循环进行数组迭代。

Just use a basic for loop for array iteration.

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