从Powershell中的列表中选择最后一项

Question

我正在尝试使用这行代码映射驱动器号,这将为我提供从d到z可用的驱动器列表.

ls function:[d-z]: -n|?{!(test-path $_)}

我想从列表中选出最后一个字母,而不是随机字母.我该怎么做呢？Powershell的新手,感谢您的帮助.

Answer 1

您可以Select-Object -Last 1在该管道的末尾使用.

Answer 2

您可以从列表的最后面开始，然后向上。

最后一项：$array[-1] 倒数第二项：$array[-2] 依此类推。

Answer 3

如果你想要更冗长,但(在我看来)可读性改进版本:

# Get all drives which are used (unavailable)
# Filter for the "Name" property ==> Drive letter
$Drives = (Get-PSDrive -PSProvider FileSystem).Name

# Create an array of D to Z
# Haven't found a more elegant version...
$Letters = [char[]]([char]'D'..[char]'Z')

# Filter out, which $Letters are not in $Drives (<=)
# Again, filter for their letter
$Available = (Compare-Object -ReferenceObject $Letters -DifferenceObject $Drives | Where {$_.SideIndicator -eq "<="}).InputObject

# Get the last letter
$LastLetter = $Available[-1]