Execute PowerShell command on selected files in Explorer

Solution 1:

HKCR:\*\shell contains what you need. Create a new key with the name of what you want to call it (eg "Rename With Date"), then a subkey called "Command" with a default value of your command.

So for example, HKCR:\*\shell\Rename With Date\Command where the (Default) value is PowerShell -Command Rename-Item "%1" ((Get-Date).ToShortDateString() + " - %1") or something should do the trick I think.

Solution 2:

It is fairly easy to add a context-menu command to selected files in File Explorer using Powershell's New-Item cmdlet to write a command line to the registry:

# Add a context-menu item named 'Foo' to the context menu of files 
# that executes a PowerShell command that - in this simple demonstration - 
# simply *echoes* the file path given, using Write-Output.
$null = New-Item -Force "HKCU:\Software\Classes\*\shell\Foo\command" | 
        New-ItemProperty -Name '(Default)' -Value `
         "$PSHOME\powershell.exe -NoProfile -NoExit -Command Write-Output \`"%1\`""

^{The above targets HKCU:\Software\Classes\*\shell (HKEY_CURRENT_USER\Software\Classes\*\shell) and therefore applies to files only; the folder-only location is HKCU:\Software\Classes\Folder\shell, and the location for both files and folders is HKCU:\Software\Classes\AllFileSystemObjects\shell.
Also note the use of -LiteralPath above, which is crucial to prevent interpretation of the * in HKCU:\Software\Classes\* as a wildcard.
Note that writing to the equivalent HKEY_LOCAL_MACHINE keys so as to make the command available to all users would require elevation (running as administrator).}

The caveat is that with this approach the command is invoked for each selected file, should multiple files be selected.

In other words: if your intent is to rename a group of files and your renaming logic requires that the group be considered as a whole, the above approach won't work.

You could try to work around that in the script itself, but that would be nontrivial.

A more robust solution is to create context-menu handlers, which requires writing "in-process Component Object Model (COM) objects implemented as DLLs" (from the docs).