How to pause with PowerShell 2.0?

Question

Alright, I'm losing it. PowerShell annoys me. I would like a pause dialogue to appear, and it will not.

PS W:\>>> $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown") Exception calling "ReadKey" with "1" argument(s): "The method or operation is not implemented." At line:1 char:23 + $host.UI.RawUI.ReadKey <<<< ("NoEcho") + CategoryInfo : NotSpecified: (:) [], MethodInvocationException + FullyQualifiedErrorId : DotNetMethodException 

Answer 1

 cmd /c pause | out-null 

(This is not a PowerShell method, but it is much wider.)

Save the trees. Use single line.

Answer 2

I think it's worth demonstrating the choice here for clarity ... then suggest a new option that, in my opinion, provides better utility.

<1> ReadKey (System.Console)

 write-host "Press any key to continue..." [void][System.Console]::ReadKey($true) 

• Advantage: accepts any key, but correctly excludes the modifier keys Shift, Alt, Ctrl.
• Disadvantage: does not work in PS-ISE.

<2> ReadKey (RawUI)

 Write-Host "Press any key to continue ..." $x = $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown") 

• Disadvantage: does not work in PS-ISE.
• Disadvantage: does not exclude modifier keys.

<3> cmd

 cmd /c Pause | Out-Null 

• Disadvantage: does not work in PS-ISE.
• Disadvantage: Apparently launches a new shell / window on first use; not noticeable on subsequent use, but still has overhead

<4> Read-Host

 Read-Host -Prompt "Press Enter to continue" 

• Advantage: Works in PS-ISE.
• Shortcoming: accepts only the Enter key.

<5> ReadKey composite

This is a composition above 1 using the ISE / kludge workaround extracted from the Adam Tech Blog offer (kindly provided by Nick from the previous comments on this subject page). I made two small improvements for the latter: a test path was added to avoid error if you use Set-StrictMode (right?), And final Write-Host to add a new line after pressing a key to place the prompt in the right place.

 Function Pause ($Message = "Press any key to continue . . . ") { if ((Test-Path variable:psISE) -and $psISE) { $Shell = New-Object -ComObject "WScript.Shell" $Button = $Shell.Popup("Click OK to continue.", 0, "Script Paused", 0) } else { Write-Host -NoNewline $Message [void][System.Console]::ReadKey($true) Write-Host } } 

• Advantage: accepts any key, but correctly excludes the modifier keys Shift, Alt, Ctrl.
• Advantage: works in PS-ISE (although only with Enter or mouse)
• Disadvantage: more than one ship!

Answer 3

I assume you want to read input from the console. If so, use Read-Host .

Answer 4

Solutions like cmd /c pause cause the new shell to start and run in the background. Although this is acceptable in some cases, it is not entirely ideal.

Solutions using Read-Host force the user to press Enter, and are in fact not a "no key."

This solution will provide you with a true “press any key to continue” interface and will not launch a new interpreter that essentially mimics the original pause command.

 Write-Host "Press any key to continue..." [void][System.Console]::ReadKey($true) 

Answer 5

In addition to Michael Sorens, answer:

<6> ReadKey in the new process

 Start-Process PowerShell {[void][System.Console]::ReadKey($true)} -wait 

• Advantage: Accepts any key, but correctly excludes Shift, Alt, Ctrl modifier keys.
• Advantage: Works in PS-ISE.