将cmd行参数传递给powershell脚本-如果没有争论，如何退出

Question

So far I have my .ps1 file with this

Param([Parameter(Mandatory=$true,ValueFromPipelin=$true)][string[]] $appPoolArray)
$zero = 0
if ($appPoolArray.length -eq $zero){
Write-Output "no app pools where selected"
exit
}
else {
foreach ($elem in $appPoolArray)
$appPool = Get-WmiObject -namespace "root\MicrosoftIISv2" -class "IIsApplicationPool" | Where-Object {$_.Name -eq "W3SVC/APPPOOLS/$elem"}
$appPool.Recycle()
Write-Output "Recycled."
Start-Sleep -Second 60
}
Write-Output "Done."
}

I would like to make it so if there is no arguments in the cmd line then it exits right away, instead it just asks me to keep adding elements into the array if I did not include arguements in the command (The command I am running in cmd line is powershell -noexit path\\script.ps1) I'm not very good with Powershell or scripts in general but I know the error is with the if statement. Help would be appreciated

Edit: I tried taking out the Write-Mandatory=$True but it now gives me an error when I dont pass any arguements

Answer 1

Take out Mandatory=$True and add a missing brace at the end of foreach.. line. In the future use indents and format your code as you will find it easier to spot these errors(or use a tool like PowerGUI( http://www.quest.com/powergui-freeware ))

Param([Parameter(ValueFromPipeline=$true)][string[]] $appPoolArray)
    if ($appPoolArray -eq $null){
        Write-Output "no app pools where selected"           
    }
    else {
        foreach ($elem in $appPoolArray){
            $appPool = Get-WmiObject -namespace "root\MicrosoftIISv2" -class "IIsApplicationPool" | Where-Object {$_.Name -eq "W3SVC/APPPOOLS/$elem"}
            $appPool.Recycle()
            Write-Output "Recycled."
            Start-Sleep -Second 60
        }
    Write-Output "Done."
    }

I changed 2nd line to if ($appPoolArray -eq $null){ as it shows your intentions more clearly but your original statement will work too.