Capturing Powershell output in C# after Pipeline.Invoke throws

Question

I'm running a Powershell test script from a C# application. The script can fail due to a bad cmdlet which causes pipe.Invoke() to throw an exception.

I'm able to capture all the information I need about the exception, but I'd like to be able to display the script's output up to that point. I haven't had any luck since results appears to be null when an exception is thrown.

Is there something I'm missing? Thanks!

m_Runspace = RunspaceFactory.CreateRunspace();
m_Runspace.Open();
Pipeline pipe = m_Runspace.CreatePipeline();
pipe.Commands.AddScript(File.ReadAllText(ScriptFile));
pipe.Commands.Add("Out-String");
try {
   results = pipe.Invoke();
}
catch (System.Exception)
{
   m_Runspace.Close();
   // How can I get to the Powershell output that comes before the exception?
}

Answer 1

Not sure if this is helpful. I am guessing you are running V1. This V2 approach doesn't throw and prints the result:

Hello World
67 errors

string script = @"
  'Hello World'
  ps | % {
    $_.name | out-string1
  }
";

PowerShell powerShell = PowerShell.Create();

powerShell.AddScript(script);
var results = powerShell.Invoke();

foreach (var item in results)
{
  Console.WriteLine(item);
}

if (powerShell.Streams.Error.Count > 0)
{
  Console.WriteLine("{0} errors", powerShell.Streams.Error.Count);
}

Answer 2

The solution I ended up using was to implement our own PSHost to handle PowerShell's output. The initial information for this came from http://community.bartdesmet.net/blogs/bart/archive/2008/07/06/windows-powershell-through-ironruby-writing-a-custom-pshost.aspx in the "Building a custom PS host" section.

In my case it did require using a custom PSHostRawUserInterface as well.

Here's the quick overview of what was done. I've only listed the function I actually implimented, but there's many that are just contain throw new NotImplementedException();

private class myPSHost : PSHost
{
   (Same as what the above link mentions)
}
private class myPSHostUI : PSHostUserInterface
{
   private myPSHostRawUI rawui = new myPSHostRawUI();

   public override void Write // all variations
   public override PSHostRawUserInterface RawUI { get { return rawui; } }

}
private class myPSHostRawUI : PSHostRawUserInterface
{
   public override ConsoleColor ForegroundColor
   public override ConsoleColor BackgroundColor
   public override Size BufferSize
}