// Declares the string array "args" to hold the
// command line arguments. Remember it will be a
// string array.
private string[] args;

public MainWindow()
{
    // Gets the command line arguments
    args = Environment.GetCommandLineArgs();

    // Shows a message box for each argument.
    // Remember that arg[0] will always be the
    // program file name in WPF
    for (int i = 0; i < args.Length; i++)
    {
      MessageBox.Show(args[i] + "\n");
    }
}