Question

I have a windows service written in C# that acts as a proxy for a bunch of network devices to the back end database. For testing and also to add a simulation layer to test the back end I would like to have a GUI for the test operator to be able run the simulation. Also for a striped down version to send out as a demo. The GUI and service do not have to run at the same time. What is the best way to achieve this duel operation?

Edit: Here is my solution combing stuff from this question , Am I Running as a Service and Install a .NET windows service without InstallUtil.exe using this excellent code by Marc Gravell

It uses the following line to test if to run the gui or run as service.

 if (arg_gui || Environment.UserInteractive || Debugger.IsAttached) 

Here is the code.

 using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Windows.Forms; using System.ComponentModel; using System.ServiceProcess; using System.Configuration.Install; using System.Diagnostics;  namespace Form_Service {    static class Program    {       ///        /// The main entry point for the application.       ///        [STAThread]       static int Main(string[] args)       {          bool arg_install =  false;          bool arg_uninstall = false;          bool arg_gui = false;          bool rethrow = false;          try          {             foreach (string arg in args)             {                switch (arg)                {                   case '-i':                   case '-install':                      arg_install = true; break;                   case '-u':                   case '-uninstall':                      arg_uninstall = true; break;                   case '-g':                   case '-gui':                      arg_gui = true; break;                   default:                      Console.Error.WriteLine('Argument not expected: ' + arg);                      break;                }             }             if (arg_uninstall)             {                Install(true, args);             }             if (arg_install)             {                Install(false, args);             }             if (!(arg_install || arg_uninstall))             {                if (arg_gui || Environment.UserInteractive || Debugger.IsAttached)                {                   Application.EnableVisualStyles();                   Application.SetCompatibleTextRenderingDefault(false);                   Application.Run(new Form1());                }                else                {                   rethrow = true; // so that windows sees error...                    ServiceBase[] services = { new Service1() };                   ServiceBase.Run(services);                   rethrow = false;                }             }             return 0;          }          catch (Exception ex)          {             if (rethrow) throw;             Console.Error.WriteLine(ex.Message);             return -1;          }       }        static void Install(bool undo, string[] args)       {          try          {             Console.WriteLine(undo ? 'uninstalling' : 'installing');             using (AssemblyInstaller inst = new AssemblyInstaller(typeof(Program).Assembly, args))             {                IDictionary state = new Hashtable();                inst.UseNewContext = true;                try                {                   if (undo)                   {                      inst.Uninstall(state);                   }                   else                   {                      inst.Install(state);                      inst.Commit(state);                   }                }                catch                {                   try                   {                      inst.Rollback(state);                   }                   catch { }                   throw;                }             }          }          catch (Exception ex)          {             Console.Error.WriteLine(ex.Message);          }       }    }     [RunInstaller(true)]    public sealed class MyServiceInstallerProcess : ServiceProcessInstaller    {       public MyServiceInstallerProcess()       {          this.Account = ServiceAccount.NetworkService;       }    }     [RunInstaller(true)]    public sealed class MyServiceInstaller : ServiceInstaller    {       public MyServiceInstaller()       {          this.Description = 'My Service';          this.DisplayName = 'My Service';          this.ServiceName = 'My Service';          this.StartType = System.ServiceProcess.ServiceStartMode.Manual;       }    }  } 

Answer 1

You basically have two choices. Either expose an API on the service which you can then call from the UI app OR enable the service to run either as a winforms app or a service.

The first option is pretty easy – use remoting or WCF to expose the API.

The second option can be achieved by moving the ‘guts’ of your app into a separate class then create a service wrapper and a win-forms wrapper that both call into your ‘guts’ class.

static void Main(string[] args) {     Guts guts = new Guts();      if (runWinForms)     {         System.Windows.Forms.Application.EnableVisualStyles();         System.Windows.Forms.Application.SetCompatibleTextRenderingDefault(false);          FormWrapper fw = new FormWrapper(guts);          System.Windows.Forms.Application.Run(fw);     }     else     {         ServiceBase[] ServicesToRun;         ServicesToRun = new ServiceBase[] { new ServiceWrapper(guts) };         ServiceBase.Run(ServicesToRun);     } }