Issue with variables within the scriptblock of Invoke-Command

Question

I seem to have a issue with getting variables in the Invoke-Command . I can't get a variable in whatever I do. When I want to use:

Invoke-Command -ComputerName $servername  { new-item -Path "$RootPathDestination" -Name $version -Itemtype directory }

I get the error:

Cannot bind argument to parameter 'Path' because it is an empty string.

And I have declared them in this script:

$version = 36
$RootPathDestination = "c:\scripts\"

Does anyone have any ideas? I am really out of options here :-(

 $svr = "SQLSERVER"
    $db = "0000 - INFRA"
    $version = 36
    $RootPathDestination = "c:\scripts\"


    # connection
    $sqlConnection = New-Object System.Data.SqlClient.SqlConnection
    $sqlConnection.ConnectionString = "Server=$svr;Database=$db;Integrated Security=True"

        $sqlConnection.Open()
         $cmd = $sqlConnection.CreateCommand()
         $cmd.CommandText ="SELECT * from infrastructure"
         $Serverinfo = $cmd.ExecuteReader()
         try
         {
             while ($Serverinfo.Read())
             {
               $servername = $Serverinfo.GetValue(1)
               Invoke-Command -ComputerName $servername  { new-item -Path "$RootPathDestination" -Name $version -Itemtype directory }
               #Invoke-Command -ComputerName $servername { Copy-Item c:\scripts\* c:\test }
               #Invoke-Command -ComputerName $servername {Import-Module WebAdministration ; New-WebApplication -force  -Site "Default Web Site" -Name 3.78 -PhysicalPath "c:\inetpub\"$version }
             }
         }
         catch
         {
           echo "Hmm strange"
         }
         finally
         {
         echo "All good!"

         echo $Version



           $sqlConnection.Close() 
         }

Answer 1

你必须使用using前缀：

Invoke-Command -ComputerName $servername  { new-item -Path "$using:RootPathDestination" -Name $using:version -Itemtype directory }

Answer 2

You are passing a scriptblock to Invoke-Command . In order to use the values of any variables defined outside that scriptblock within the scriptblock, you need to refer to them as $using:variablename (in your example, $using:RootPathDestination . See Get-Help about_Remote_Variables .