How can I associate a file type with a powershell script?

Question

I have a very powershell script that works perfectly and does:

Param(
  [string]$fileName
) 

echo "Woo I opened $fileName"

When I run it on the command line, it works:

my-script.ps1 .\somefile

Returns:

Woo I opened somefile

I would like to associate my-script.ps1 with a particular file type. I am attempting to do this via 'Open With' However:

• Windows doesn't include Powershell scripts as 'Programs' (though it considers CMD and batch scripts as 'Programs')

• When I pick 'All Files' instead, and pick my powershell script, Windows shows this message

How can I associate a file type with a Powershell script?

Answer 1

Use the proper tools for the job:

cmd /c assoc .fob=foobarfile
cmd /c ftype foobarfile=powershell.exe -File `"C:\path\to\your.ps1`" `"%1`"

Note that both assoc and ftype are CMD-builtins, so you need to run them via cmd /c from PowerShell.

For files without extension use this association:

cmd /c assoc .=foobarfile

Answer 2

I don't think you can do it through Windows UI.

The goal here is to associate a type with powershell.exe, arguments to which will be

1. The powershell script
2. The target filename

To do this

1. Launch Regedit.exe. //disclaimer: you are editing Windows registry. Here be tigers.
2. Go to HKEY_CLASSES_ROOT (admin access, for all users) or HKEY_CURRENT_USER\SOFTWARE\Classes
3. Create a key named .<extension>, e.g. if you want to associate *.zbs - create a key .zbs
4. Set it's (default) value to something like zbsfile -- this is a reference linking your extension to a filetype.
5. Create a key called zbsfile - this is your filetype
6. Set (default) value to something readable, e.g. "This file is ZBS."
7. Underneath create a tree of keys (examples are all around):

zbsfile shell open command

8. Under command, set (default) value to e.g.
   powershell.exe -File "C:\path\to your\file.ps1" "%1"
   where %1 means the file user clicked

That should work.

EDIT: or (crazy idea), create a bat file doing just powershell.exe -File "C:\path\to your\file.ps1" "%%1" and select it in Windows UI...