JSpot

I recently had a case where I needed to handle a series of command line arguments. I needed to know if flagA had been set with flagB, but not with flagC and flagD.

Ripping through the list of command line arguments is easy enough, but tedious, so I wrote my own CommandLine class that lets me reference flags by name. For instance, if I need to check to see if flagA exists, I can just say cmd.ContainsKey("flagA").

The best part is that it only modified my master source by one line:

CMD cmd = new CMD(args);

I thought that this little ditty -- while being trivial in concept -- was worth sharing. If you find it useful, let me know. Also, if you have comments, feel free to post them.

    public class CMD : Hashtable
    {
        public CMD(string[] args)
        {
            if (args == null) return;

            for (int x = 0; x < args.Length; x++)
            {
                if (args[x].StartsWith("-") || args[x].StartsWith("/"))
                {
                    // take off the "-"
                    string key = ((string)args[x]).Substring(1);

                    // We have a flag. Is it a TF or a value flag?
                    if ((x < args.Length - 1) && (!args[x + 1].StartsWith("-")))
                    {
                        // VALUE flag                        
                        this[key] = args[x + 1];
                        x++;
                    }
                    else
                    {
                        // True/False flag
                        this[key] = true;
                    }
                }
            }
        }
    }

Once you've defined the class, accessing the command line arguments becomes trivial. In the example below, I have a simple console application that needs command line parsing. Once CMD is initialized, I can access CMD from anywhere, and access all of my command line parameters by name.

    class Program
    {
        static CMD cmd;

        static void Main(string[] args)
        {
            cmd = new CMD(args);

            // Do some magic stuff here
        }
    }

Labels: C-Sharp