Parallel programming in C#

Question

I\'m interested in learning about parallel programming in C#.NET (not like everything there is to know, but the basics and maybe some good-practices), therefore I\'ve decide

Answer 1

Interesting problem. I came up with two approaches. The first is based on PLinq and the second is based on te Rx Framework.

The first one iterates through the files in parallel. The second one generates asynchronously the files from the directory.

Here is how it looks like in a much simplified version (The first method does require .Net 4.0 since it uses PLinq)

string direcory = "Mydirectory";
    var jpegFiles = System.IO.Directory.EnumerateFiles(direcory,"*.jpg");


    // --  PLinq --------------------------------------------
    jpegFiles
    .AsParallel()
    .Select(imageFile => new {OldLocation = imageFile, NewLocation = GenerateCopyLocation(imageFile) })
    .Do(fileInfo => 
        {
            if (!File.Exists(fileInfo.NewLocation ) || 
                (File.GetCreationTime(fileInfo.NewLocation)) != (File.GetCreationTime(fileInfo.NewLocation)))
                File.Copy(fileInfo.OldLocation,fileInfo.NewLocation);
        })
    .Run();

    // -----------------------------------------------------


    //-- Rx Framework ---------------------------------------------
    var resetEvent = new AutoResetEvent(false);
    var doTheWork =
    jpegFiles.ToObservable()
    .Select(imageFile => new {OldLocation = imageFile, NewLocation = GenerateCopyLocation(imageFile) })
    .Subscribe( fileInfo => 
        {
            if (!File.Exists(fileInfo.NewLocation ) || 
                (File.GetCreationTime(fileInfo.NewLocation)) != (File.GetCreationTime(fileInfo.NewLocation)))
            File.Copy(fileInfo.OldLocation,fileInfo.NewLocation);
        },() => resetEvent.Set());

    resetEvent.WaitOne();
    doTheWork.Dispose();

    // -----------------------------------------------------