It’s very simple, first get yourself a program class, which contains some properties you want the user able to set via the commandline and apply the Parameter attribute:

class CopyProgram
{
    private string _Source;
    [Parameter(Position = 0, IsMandatory = true)]
    public string Source
    {
        get { return _Source;}
        set { _Source = value; }
    }
    private string _Target;

    [Parameter(Position = 1, IsMandatory = true)]
    public string Target
    {
        get { return _Target;}
        set { _Target= value; }
    }

    private bool _WalkRecursivly;
    [Parameter(Name = "recursivly")]
    public bool WalkRecursivly
    {
        get { return _WalkRecursivly;}
        set { _WalkRecursivly= value; }
    }   

    static void Main(string[] args)
    {
        new Program().Run(args);
    }

    void Run(string[] args)
    {
        CommandLine.ParseCommandLine(args, this);

        // Do stuff here
    }
}

The CommandLine.ParseCommandLine function takes care of parsing the command line string array and filling the required properties of the class provided.

You can call this program in a few different ways:

copy.exe c:\source.txt c:\target.txt
copy.exe -s c:\source.txt -target c:\target.txt
copy.exe -targ c:\target.txt c:\source.txt  -r

Although it only required around 250 lines of code it certainly is an enourmous time safer and makes stuff a lot easier for the user.

At the moment I’m programming a few small utilities and will change the code a bit and fix some bugs if any.

For those interesting in testing it themselves (I encourage it), just download the Intrepid.Corelib .net 2 assembly*. The classes required are in the Intrepid.Automation namespace. Please send any bug reports to: bas.westerbaan@gmail.com.

(* You may use everything in the Intrepid.Corelib assembly freely for non-commercial open-source usage. Do not modify or reverse engineer the assembly in any way.)

Update:
Got rid of some bugs and added the RequiresValue property to ParameterAttribute. Will replace lateron with Type, this allows you to use -e bleh where -e takes no value and bleh is interpreted as a nameless parameter. Will add alliases too.