如何在Powershell中创建数组的空数组? [英] How do I create an empty array of arrays in Powershell?

问题描述

我想在Powershell中创建一个空数组，以容纳值的元组"(数组是不可变的).

I want to create an empty array of arrays in Powershell to hold "tuples" of values (arrays are immutable).

因此，我尝试以下操作:

Therefore I try something like:

$arr的类型为Object[].我已经读到+= @(1,2)将给定的元素(即@(1,2))附加到$arr(实际上是创建一个新数组).但是，在这种情况下，数组似乎是串联在一起的，为什么?

The type of $arr is Object[]. I've read that += @(1,2) appends the given element (i.e. @(1,2)) to $arr (actually creates a new array). However, in this case it seems that the arrays are concatenated, why?

$arr = @()
$arr += @(1,2)
$arr.Length // 2 (not 1)

如果执行以下操作，则$arr似乎包含两个数组@(1,2),@(3,4)，这就是我想要的:

If I do as follows, it seems that $arr contains the two arrays @(1,2),@(3,4), which is what I want:

$arr = @()
$arr += @(1,2),@(3,4)
$arr.Length // 2

如何初始化数组的空数组，以便一次可以添加一个子数组，例如$arr += @(1,2)?

How do I initialize an empty array of arrays, such that I can add one subarray at a time, like $arr += @(1,2)?

推荐答案

Bruce Payette的答案将起作用.语法对我来说似乎有点尴尬，但它确实有效.至少不是Perl.

The answer from Bruce Payette will work. The syntax seems a bit awkward to me, but it does work. At least it is not Perl.

执行此操作的另一种方法是使用ArrayList.对我来说，这种语法更清晰，并且更可能在六个月内被另一个开发人员(或我本人)理解.

Another way to do this would be with an ArrayList. To me, this syntax is more clear and more likely to be understood by another developer (or myself) in six months.

[System.Collections.ArrayList]$al = @()

$al.Add(@(1,2))
$al.Add(@(3,4))

foreach ($e in $al) {
    $e
    $e.GetType()
}

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