在PowerShell脚本中验证文件路径时遇到问题

Question

我在验证脚本中的文件输入时遇到了一些麻烦。使用以下函数

Function pathtest {
[CmdletBinding()]
param (
[ValidateScript({
if (-Not ($_ | Test-Path -PathType Leaf) ) {
throw "The Path argument must be a file. Folder paths are not allowed."
}
return $true
})]
[System.IO.FileInfo]$Path
)
Write-Host ("Output file: {0}" -f $Path.FullName)
}

然后我用这两个输入文件调用函数

pathtest -Path c:temptest.txt
pathtest -Path c:temptest.csv

第一个(test.txt)返回路径，但第二个(test.csv)返回错误:

PS C:> pathtest c:ittest.txt
Output file: c:ittest.txt
PS C:> pathtest c:ittest.csv
pathtest : Cannot validate argument on parameter 'Path'. The Path argument must be a file. Folder paths are not
allowed.
At line:1 char:10
+ pathtest c:ittest.csv
+          ~~~~~~~~~~~~~~
+ CategoryInfo          : InvalidData: (:) [pathtest], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationError,pathtest

你知道这是怎么回事吗?

Answer 1

Test-Path-Leaf在指定路径不存在时也返回$false

因此，您需要单独测试是否存在，以便区分一个恰好是文件夹的存在路径和一个不存在的路径。

试试下面的命令:

Function pathtest {
[CmdletBinding()]
param (
[ValidateScript({
$item = Get-Item -ErrorAction Ignore -LiteralPath $_
if (-not $item) {
throw "Path doesn't exist: $_"
}
elseif ($item.PSIsContainer) {
throw "The Path argument must be a file. Folder paths are not allowed."
}
return $true
})]
[System.IO.FileInfo] $Path
)
Write-Host ("Output file: {0}" -f $Path.FullName)
}