Welcome to DataflowEx

DataflowEx is a collection of extensions to TPL Dataflow library with Object-Oriented Programming in mind. It does not replace TPL Dataflow but provides abstraction/management on top of dataflow blocks to make your life easier.

If you are not familiar with TPL Dataflow yet, please take your time to watch two videos:

Beginner (15min): http://channel9.msdn.com/posts/TPL-Dataflow-Tour

Advanced (63min): http://channel9.msdn.com/posts/TPL-Dataflow-Tour

And detailed documentation here: http://msdn.microsoft.com/en-us/library/hh228603(v=vs.110).aspx

So, what's wrong with TPL Dataflow? Nothing. The library from Microsoft library looks simply great. However, in the tough real world there are some obstacles when we apply RAW TPL Dataflow. Let's look at an example:

var splitter = new TransformBlock<string, KeyValuePair<string, int>>(
    input =>
        {
            var splitted = input.Split('=');
            return new KeyValuePair<string, int>(splitted[0], int.Parse(splitted[1]));
        });

var dict = new Dictionary<string, int>();
var aggregater = new ActionBlock<KeyValuePair<string, int>>(
    pair =>
        {
            int oldValue;
            dict[pair.Key] = dict.TryGetValue(pair.Key, out oldValue) ? oldValue + pair.Value : pair.Value;
        });

splitter.LinkTo(aggregater, new DataflowLinkOptions() { PropagateCompletion = true});

splitter.Post("a=1");
splitter.Post("b=2");
splitter.Post("a=5");

splitter.Complete();
aggregater.Completion.Wait();
Console.WriteLine("sum(a) = {0}", dict["a"]); //prints sum(a) = 6