How to Properly Pause a PowerShell Script

When I first learned about PowerShell, I immediately wanted to convert my batch files into PowerShell scripts and then enhance them with additional features. When I started that process, I quickly learned that PowerShell didn’t have anything equivalent to cmd.exe’s “Pause” command. I looked for a solution online and found the Microsoft TechNet article Windows PowerShell Tip: Press Any Key to Continue. This is the solution recommended by the article:

Write-Host "Press any key to continue ..."

$x = $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")

However, the above solution has two things wrong with it:

• It doesn’t work from within Windows PowerShell ISE
• Unlike cmd.exe’s “Pause” command, pressing keys like Ctrl and Alt causes the script to continue

To fix these two issues, I decided to write my own “Pause” function:

Function Pause ($Message = "Press any key to continue . . . ") {
	If ($psISE) {
		# The "ReadKey" functionality is not supported in Windows PowerShell ISE.

		$Shell = New-Object -ComObject "WScript.Shell"
		$Button = $Shell.Popup("Click OK to continue.", 0, "Script Paused", 0)

		Return
	}

	Write-Host -NoNewline $Message

	$Ignore =
		16,  # Shift (left or right)
		17,  # Ctrl (left or right)
		18,  # Alt (left or right)
		20,  # Caps lock
		91,  # Windows key (left)
		92,  # Windows key (right)
		93,  # Menu key
		144, # Num lock
		145, # Scroll lock
		166, # Back
		167, # Forward
		168, # Refresh
		169, # Stop
		170, # Search
		171, # Favorites
		172, # Start/Home
		173, # Mute
		174, # Volume Down
		175, # Volume Up
		176, # Next Track
		177, # Previous Track
		178, # Stop Media
		179, # Play
		180, # Mail
		181, # Select Media
		182, # Application 1
		183  # Application 2

	While ($KeyInfo.VirtualKeyCode -Eq $Null -Or $Ignore -Contains $KeyInfo.VirtualKeyCode) {
		$KeyInfo = $Host.UI.RawUI.ReadKey("NoEcho, IncludeKeyDown")
	}

	Write-Host
}

Here’s the minified version:

Function Pause($M="Press any key to continue . . . "){If($psISE){$S=New-Object -ComObject "WScript.Shell";$B=$S.Popup("Click OK to continue.",0,"Script Paused",0);Return};Write-Host -NoNewline $M;$I=16,17,18,20,91,92,93,144,145,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183;While($K.VirtualKeyCode -Eq $Null -Or $I -Contains $K.VirtualKeyCode){$K=$Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")};Write-Host}

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