Execute PowerShell from C# in non-interactive mode

Question

I am running some PowerShell scripts in C# using the System.Management.Automation namespace. This works perfectly, except when I invoke the script, I very briefly see a command window flash onto the screen and then disappear. This behavior is not acceptable in my application.

I can avoid this behavior by launching a new Process and setting CreateNoWindow=true, however I would really prefer to use the managed PowerShell library. How can I do this in a non-interactive way that does't flash on the screen?

An example of some PowerShell that causes the window flash:

using (PowerShell ps = PowerShell.Create())
{
    ps.AddCommand(@"Get-WindowsUpdateLog");
    ps.AddParameter(@"-LogPath", @"C:\WindowsUpdate.Log");
    var psOutput = ps.Invoke();
}

i think you need a custom runspace msdn.microsoft.com/en-us/library/dn569260(v=vs.85).aspx — pm100
– pm100, Commented Apr 24, 2018 at 21:13
I took a look at the custom runspace and initial session state but couldn't find anything pertaining to UI interactivity. — WillowDweller
– WillowDweller, Commented Apr 24, 2018 at 21:27

Bruce Payette · Accepted Answer · 2018-04-24 22:05:27Z

2

I believe the flash you're seeing is because the Get-WindowsUpdateLog function internally calls tracerpt.exe which is a console app. Running a console app from a GUI results in a flash. (You'll see the same flash if you run GetWindowsUpdateLog from the ISE.) Unfortunately there isn't much you can do about it. You could modify you Win32 app to allocate a console handle at startup controlling when you see the flash but you'll still see it.

answered Apr 24, 2018 at 22:05

Bruce Payette

2,67912 silver badges8 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Execute PowerShell from C# in non-interactive mode

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related