Is it possible to build a Console app that does not display a console Window when double-clicked?

So, I've written tools with both a GUI and a CLI. The hard part was figuring out which one to open - in our case, though, the CLI version had required parameters, so I just opened the GUI if there weren't any parameters. Then, if they did want a console, call a function that looks something like:

private const int ATTACH_PARENT_PROCESS = -1;
private const int ERROR_INVALID_HANDLE = 6;
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool AttachConsole(int dwProcessId);
[DllImport("kernel32.dll")]
static extern bool AllocConsole();
[DllImport("kernel32.dll")]
static extern bool FreeConsole();

private static bool StartConsole()
{
  if (!AttachConsole(ATTACH_PARENT_PROCESS)) // try connecting to an existing console  
  {  
      if (Marshal.GetLastWin32Error() == ERROR_INVALID_HANDLE) // we don't have a console yet  
      {  
          if (!AllocConsole()) // couldn't create a new console, either  
              return false;  
      }
      else
          return false; // some other error
  }
  return true;
}

Returns whether the console was created. Don't forget to FreeConsole() when you're done!

In our case, of course, if we don't create a console, we create a GUI. It'd be just as easy to create either a console or no UI, though.

EDIT: That totally didn't answer the question in the edit that wasn't there when I started writing that, of course. Other than that our hack was just checking whether it was called with command-line parameters or not.

Just build it as a Windows Forms app, but don't give it a GUI. Unfortunately then you won't get any console output when it's run from the command line either... is that a problem?

See Can a Win32 console application detect if it has been run from the explorer or not?

Or I think the official way is to check the parent process is cmd.exe or explorer.exe