How to convert C# code to a PowerShell Script?

I know you're looking for something that somehow converts C# directly to PowerShell, but I thought this is close enough to suggest it.

In PS v1 you can use a compiled .NET DLL:

PS> $client = new-object System.Net.Sockets.TcpClient
PS> $client.Connect($address, $port)

In PS v2 you can add C# code directly into PowerShell and use it without 'converting' using Add-Type (copied straight from MSDN )

C:\PS>$source = @"
public class BasicTest
{
    public static int Add(int a, int b)
    {
        return (a + b);
    }

    public int Multiply(int a, int b)
    {
        return (a * b);
    }
}
"@

C:\PS> Add-Type -TypeDefinition $source

C:\PS> [BasicTest]::Add(4, 3)

C:\PS> $basicTestObject = New-Object BasicTest 
C:\PS> $basicTestObject.Multiply(5, 2)

There is a Reflector add-in for PowerShell that will allow you to see the corresponding PowerShell script for static methods on classes

There's a good post with the example: http://blogs.msmvps.com/paulomorgado/2009/09/17/powershell-for-the-net-developer/.

PowerShell Pro Tools for Visual Studio have a feature to convert C# code in a PowerShell script.