How does a C# runspace/pipeline execute a powershell script?

Question

There are so many questions and answers about how to execute a powershell script from C# code, but I would like to know how exactly the runspace/pipeline performs the execution of the .ps1 file.

The context in which I am asking is this: I've built a basic asp.net front end for a powershell script that sets up a new website. It creates the site in IIS and sets up wwwroot folders, log folders, an AD user and everything else that it needs. It works perfectly when I run it as an admin in powershell. However, when I run it through my C# pipeline, it breaks the pipe with a parameter binding exception.

I'm not after an answer to this specific problem, I'm just looking for an explanation of how the pipeline executes my file so that I can have a better understanding of what exactly is going on.

Answer 1

It's not a complete explanation of how the runspace works, but I've written a blog post covering the main bits.

Also a snippet from one of the msdn pages on how powershell works:

The Powershell runtime is invoked as a runspace and will, by default, process commands synchronously and deliver the results of processing to the host application so that they can be returned to the user.

Answer 2

Have you tried using ILSpy or opening the class in Class View to see the code for the class? I do this all the time to see how Microsoft implements a particular class. I would paste the code here if it was a short answer, but there is a lot to the System.Management.Automation.Runspaces or Microsoft.Powershell namespaces. Take a look for yourself, and you will be able to see exactly how Microsoft implements the execution of Powershell scripts.

Hope this helps.