PowerShell CmdLet reflecten

Meistens muss ich alles ganz genau wissen: Z.B. wie ein spezielles PowerShell-CmdLet implementiert ist.
Mittels des folgenden kleinen Skriptes​ kann man ganz schnell die implementierende DLL zu einem CmdLet finden und notfalls auch schon mal einen decompiler starten.​
Die Inspiration kommt von OISIN GREHAN​.

<#  
.SYNOPSIS  
    Run reflection on a given commandlet
.DESCRIPTION  
    Run reflection on any CmdLet
.NOTES  
    This code was heavily inspired from OISIN GREHAN, see http://www.nivot.org/post/2008/10/30/ATrickToJumpDirectlyToACmdletsImplementationInReflector
.Example
    Get-Command Get-ChildItem | Reflect-Cmdlet -Reflect ShowDllOnly
.Example
    Reflect-Cmdlet -CmdLet (Get-Command Get-ChildItem) -Reflect ShowDllOnly
#>
[CmdletBinding()]
param(
    [Parameter(Position=0, 
        Mandatory=$true, 
        ValueFromPipeline=$true,
        ValueFromPipelineByPropertyName=$true,
        HelpMessage = "The CmdLet to reflect")]
    [Management.Automation.CommandInfo]$CmdLet,
 
    [Parameter(HelpMessage = "Which reflector to use.. ")]
    [ValidateSet("ShowDllOnly", "Reflector", "JustDecompile", "ILSpy")]
    [string]$Reflect = "ShowDllOnly"
)
      
# resolve to command if this is an alias  
while ($CmdLet.CommandType -eq "Alias") {  
    $def = $CmdLet.definition;
    Write-Verbose "$CmdLet is an alias. Using Definition: $def";
    $CmdLet = Get-Command $def
}  
Write-Verbose "Reflecting $CmdLet.";
       
$name = $CmdLet.ImplementingType      
$DLL = $CmdLet.DLL  
if($DLL -eq $null) {
    Write-Warning "$CmdLet is not implemented in any DLL. Possibly a script?";
    if($CmdLet.Path -ne $null) {
         Write-Warning "Have a look at: $($CmdLet.Path)"
    }
    #$CmdLet | gm
    Exit;
}
 
Write-Verbose "Type:$name, DLL:$DLL";
switch ($Reflect) {
    "ShowDllOnly" {
        Write-Output "$CmdLet is implemented in $name in the dll:$DLL";
    }
    "Reflector" {
        if (-not (Get-Command reflector.exe -ErrorAction SilentlyContinue)) {  
            throw "Reflector.exe is not in your path."
        }  
        Write-Verbose "Starting Reflector.";
        reflector /select:$name $DLL
    }
    "JustDecompile" {
        $regKey = Get-Item HKCU:\Software\Telerik\JustDecompile -ErrorAction SilentlyContinue
        if($regKey -eq $null) {
            throw "It seems JustDecompile is not installed."
        }
        $exe = $regKey.GetValue("ExecutablePath") ;
        Write-Verbose "invoking $exe";
        &$exe """$DLL""" ; #TODO: select the right type...
    }
    "ILSpy" {
      if (-not (Get-Command ilspy.exe -ErrorAction SilentlyContinue)) {  
            throw "ilspy.exe is not in your path."
        }  
      Write-Verbose "Starting ILSpy.";
      ilspy $DLL /navigateTo:T:$name
    }
}