2

Disclaimer : I am the epitome of a scipting/Powershell rookie, so please bear with me.

I've written a script to return the Active Directory username of any user currently logged into a given workstation.

$input = Read-Host "Workstation Name"
$domain = ".*****.***.com"
$computer = $input + $domain
$list = gwmi win32_computersystem -comp $computer | select Username,Caption
Write-Output $list

However, if I run this from a pinned script in the taskbar, the Powershell window closes before I have a chance to view the results.

I have tried method 2 and 3 from this post, but to no avail. Method 2 prompts for user input before the results are displayed instead of after, even when the code for the prompt is added at the end of the script.

Any help would be greatly appreciated.

kyledmontague
  • 31
  • 4

2 Answers2

2

Method 2 from the linked post - i.e., waiting for the user to press a key before exiting the script - can be used, but it requires additional effort:

End your script as follows in order to see the value of $list before the pause command prompts:

$list | Out-Host  # Force *synchronous* to-display output.
pause             # Wait for the user to press Enter before exiting.

Note: pause in PowerShell is simply a function wrapper around Read-Host as follows: $null = Read-Host 'Press Enter to continue...' Therefore, if you want to customize the prompt string, call Read-Host directly.

This answer explains why the use of Out-Host (or Format-Table) is necessary in this case; in short:

  • In PSv5+, an implicitly applied Format-Table command asynchronously waits for up to 300 msecs. for additional pipeline input, in an effort to derive suitable column widths from the input data.

    • Because you use Write-Output output objects without predefined formatting data that have 2 properties (4 or fewer ), tabular output is implicitly chosen, and Format-Table is used behind the scenes, asynchronously.

    • Note: The asynchronous behavior applies only to output objects for whose types formatting instructions aren't predefined (as would be reported with Get-FormatData <fullOutputTypeName>); for instance, the output format for the System.Management.Automation.AliasInfo instances output by Get-Alias is predefined, so Get-Alias; pause does produce output in the expected sequence.

  • The pause command executes before that waiting period has elapsed, and only after you've answered the prompt does the table print, after which point the window closes right away.

  • The use of an explicit formatting command (Out-Host in the most generic case, but any Format-* cmdlet will do too) avoids that problem by producing display output synchronously, so that the output will be visible by the time pause displays its prompt.

mklement0
  • 382,024
  • 64
  • 607
  • 775
-1

I had the same problem for scripts that I'm executing "on demand". I tend to simply add a Read-Host at the end of the script like so

$str = "This text is hardly readable because the console closes instantly" 
Write-Output $str

Read-Host "Script paused - press [ENTER] to exit"
Razorfen
  • 423
  • 4
  • 12
  • Since `Write-Output $list` in the OP's case - due to the specific data being output - results in _asynchronous_ output, this won't work as intended: the `Read-Host` prompt will show _before_ the `Write-Output` output. To put it differently: this won't work for the OP and generally _may or may not work_ - it depends on the type of the data being output. See https://stackoverflow.com/a/43691123/45375 – mklement0 Sep 10 '19 at 13:56