有一个脚本具有CmdletBinding属性，这实际上使它成为一个"高级"脚本。在该脚本中，我正在并行处理管道中的数据，并且我希望在将-WhatIf参数传递给脚本调用时，将其向下传递给处理脚本块。
简化代码：

#Requires -Version 7.2
[CmdletBinding(SupportsShouldProcess = $true)]
param()

Get-ChildItem | ForEach-Object -Parallel {
    if ($PSCmdlet.ShouldProcess("target", "operation")) {
        Write-Host "Processing"
    }
}

PS C:\> script.ps1 -WhatIf
InvalidOperation: 
Line |
   2 |      if ($PSCmdlet.ShouldProcess("target", "operation")) {
     |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | You cannot call a method on a null-valued expression.

这不起作用，因为脚本块中没有定义$PSCmdlet。
当我用($using:PSCmdlet)替换$PSCmdlet时，我得到另一个错误（仅当提供-WhatIf时）：

MethodInvocationException: 
Line |
   2 |      if (($using:PSCmdlet).ShouldProcess("target", "operation")) {
     |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | Exception calling "ShouldProcess" with "2" argument(s): "The WriteObject and WriteError methods cannot be called from outside the overrides of the BeginProcessing, ProcessRecord, and EndProcessing methods, and they can only be called from within the same thread. Validate that the cmdlet makes these calls correctly, 
or contact Microsoft Customer Support Services."

显然，这是因为脚本块是在seaprate线程中执行的（"它们只能从同一个线程中调用"）。

• • 如何正确处理Foreach-Object -Parallel脚本块中的-WhatIf？**

我读过this official article，看到了PowerShell问题#13816的评论。可能是另一个相关问题：#14984.
作为旁注：在这种情况下，将-WhatIf指定为ForEach-Object本身不会产生任何影响。www.example.comhttps://thedavecarroll.com/powershell/foreach-object-whatif/#script-blocks-and--whatif