C＃在两个不同的Windows窗体之间使用互斥体有条件地执行方法

Question

I have two different windows forms applications in C# that run off of different programs. One of the windows is supposed to update a folder with content in the background. The other form either sits idle in a menu, or plays a game that relies on the content that has been downloaded in the background.

My issue occurs when the user plays the game while the content is being updated in the other form.

I have been looking into using Mutexes to communicate between the two forms so that when the user is in the game on the main form, the background form does not update any content until the user exits the game.

I have never used Mutexes before and I am looking for some help setting them up.

This is the constructor of my background form.

    /// <summary>
    /// Initialises an instance of the <see cref="GameReviewManager" /> class.
    /// </summary>
    public GameReviewManager()
    {
        _initialStartup = false;

        InitializeComponent();

        _launcher = new Process();
        _launcher.StartInfo.FileName = "GameReviewLauncher";
        _launcher.EnableRaisingEvents = true;
        _launcher.Exited += LauncherExited;

        if (!GamesFolderEmpty())
        {
            _launcher.Start();
            _initialStartup = true;
        }
        else
        {
            textLabel.Text = "Copying content, please wait.";
        }
    }

It monitors the process main form.

Here is the method that updates the context while the background form is running, it is called from the Shown event.

    /// <summary>
    /// Monitors the directory at path, copies any changes made.
    /// </summary>
    /// <param name="path">The path to monitor.</param>
    private void MonitorDirectory(string path)
    {
        //Now Create all of the directories
        foreach (string dirPath in Directory.GetDirectories(path, "*", SearchOption.AllDirectories))
        {
            Directory.CreateDirectory(dirPath.Replace(path, GamesDirectory));
        }

        //Copy all the files & Replaces any files with the same name
        foreach (string newPath in Directory.GetFiles(path, "*", SearchOption.AllDirectories))
        {
            if (newPath.Substring(newPath.Length - 4) != ".ini")
            {
                string destination = newPath.Replace(path, GamesDirectory);
                File.Copy(newPath, newPath.Replace(path, GamesDirectory), true);
                Console.WriteLine("File added: {0}", destination);

                if (!string.IsNullOrWhiteSpace(progressTextBox.Text))
                {
                    progressTextBox.AppendText("\r\n" + $"File added: {destination}");
                    progressTextBox.ScrollToCaret();
                }
                else
                {
                    progressTextBox.AppendText($"File added: {destination}");
                    progressTextBox.ScrollToCaret();
                }
            }
        }

        progressTextBox.AppendText("\r\n\r\n" + "Content copied successfully.");
        progressTextBox.ScrollToCaret();

        FileSystemWatcher fileSystemWatcher = new FileSystemWatcher();
        fileSystemWatcher.Path = path;
        fileSystemWatcher.Created += FileSystemWatcherCreated;
        fileSystemWatcher.Renamed += FileSystemWatcherRenamed;
        fileSystemWatcher.Deleted += FileSystemWatcherDeleted;
        fileSystemWatcher.Changed += FileSystemWatcherChanged;
        fileSystemWatcher.EnableRaisingEvents = true;
    }

I am not sure how to implement the mutex into this code to not allow the content to be updated if the process from the constructor is being run.

Any help would be appreciated. :)

Answer 1

Program 1

public void DownloadForm1()
{
   using (var m = new Mutex(true, "SomeAwesomeName"))
   {
      m.WaitOne();

      try
      {
         // code to protect here
      }
      finally
      {
         m.ReleaseMutex();
      }
   }
}

Program 2

public void ProcessForm2()
{
   using (var m = new Mutex(true, "SomeAwesomeName"))
   {
      m.WaitOne();

      try
      {
         // code to protect here
      }
      finally
      {
         m.ReleaseMutex();
      }
   }
}