Passing parameters to -EncodedCommand

When invoking PowerShell from cmd/bat files -EncodedCommand is a great way to pass the actual PowerShell code to powershell.exe without worrying about escaping various special characters. This allows you to have just a single batch file (with no external PowerShell scripts whatsoever) which has PowerShell code right inside the file which looks something like:


What I was recently pointed to, is that this approach has one limitation: how do you pass parameters to this PowerShell code? For example, say, cmd file gets parameters from command-line and wants to pass them to PowerShell – you obviously don’t know the values in advance so you cannot pre-encode them.

The easiest way that I found is: simply put the value from cmd file to a temporary file, and then read the file from PowerShell code.

So, for illustration purpose, my super-advanced PowerShell script will simply output the parameters:

    $params = Get-Content $env:TEMP\params.txt
    "See which parameters PowerShell got: $params"

As you can see, I am getting the parameters by reading the content of pre-defined file in %TEMP% location.

Now, let’s encode this by running:

$code = {

    $params = Get-Content $env:TEMP\params.txt
    "See which parameters PowerShell got: $params"


In my case I got:


Now we are ready to put this into cmd:

echo %* > %TEMP%\params.txt


Basically, all I do is write the command-line arguments which the batch file got to a temporary file, and then invoke our PowerShell script.

And here’s the proof that this actually works:

c:\Scripts>pass-params.cmd Here are my parameters!

c:\Scripts>echo Here are my parameters! 1>C:\Users\dsotniko\AppData\Local\Temp\

c:\Scripts>powershell.exe -EncodedCommand DQAKAA0ACgAJACQAcABhAHIAYQBtAHMAIAA9A

See which parameters PowerShell got: Here are my parameters!

Now you can have a single batch file, encapsulating PowerShell code and capable of passing parameters to it!


5 Responses to “Passing parameters to -EncodedCommand”

  1. 1 Rich Beckett July 7, 2011 at 9:38 pm

    That was very interesting, helpful and instructive. I believe I saw a post recently regarding active Roles server where someone wanted to do exactly this, pass arguments which included curly braces. I now have amuch better understanding of some of the finer aspects of PowerShell


  2. 2 Anonymous July 2, 2013 at 12:36 am

    Or you could look at it the other way and facepalm. Why is it so hard to escape characters in Powershell? And why is Windows *so* bad at validating input and guarding against attacks?

  3. 3 John Hofmann November 10, 2017 at 1:21 pm

    I know this isn’t exactly timely, but while researching this problem, I found your blog, and thought I’d share the method I came up with to do this without the need to create any extra files.

    You can simply set the variables in your batch script:


    You can then account for the variables ahead of time in your PowerShell script before encoding it:

    If ($env:VARIABLE1) {Write-Output $env:VARIABLE1}

    • 4 Lee Fitzsimmons November 13, 2017 at 6:43 am

      Here’s another variation I just finished so thought I share as well – pipe the parameters via echo eg:

      echo -p1 this -p2 is -p3 a -p4 test | powershell.exe -encodedcommand “thebase64encodedscript”

      Then at the top of your encoded powershell script, something like the following to read in your parameters.

      $params = @{}
      $curparam = “”

      $pr = [Console]::In.ReadLine()
      $pr = $pr -replace ‘\s+$’, ”
      $a = $pr | Select-String -Pattern ‘(?:^| )(\”(?:[^\”]+|\”\”)*\”|[^ ]*)’ -AllMatches

      foreach($x in $a.Matches) {

      $n = $($x -replace ‘^\s+’, ”) -replace ‘\s+$’, ”
      if($n -match (‘\-[0-9A-z]+’)) {
      $curparam = $n
      } else {
      if(-not [string]::IsNullOrEmpty($curparam)) {
      $params.add($curparam , $n)

      write-host $params.’-p1′

      Your parameters are then accessible via the arraylist $params.
      Credit for the regex goes to jimplode:

      in answer to anon , the specific use case for this is that in SCCM, powershell scripts in task sequences must be taken from a package. SCCM does however provide a way to execute a regular command, so being able to wrap the powershell script this way circumvents the need to create a package for simple one off scripts.

      • 5 Lee Fitzsimmons November 13, 2017 at 6:49 am

        Note that the above only works when executed from cmd, not a powershell prompt. In powershell, in.readline will take each space-separated item echoed as a separate line. the code can be easily modified for this scenario

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© 2007-2014 Dmitry Sotnikov

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