Book Image

Reactive Programming for .NET Developers

Book Image

Reactive Programming for .NET Developers

Overview of this book

Reactive programming is an innovative programming paradigm focused on time-based problem solving. It makes your programs better-performing, easier to scale, and more reliable. Want to create fast-running applications to handle complex logics and huge datasets for financial and big-data challenges? Then you have picked up the right book! Starting with the principles of reactive programming and unveiling the power of the pull-programming world, this book is your one-stop solution to get a deep practical understanding of reactive programming techniques. You will gradually learn all about reactive extensions, programming, testing, and debugging observable sequence, and integrating events from CLR data-at-rest or events. Finally, you will dive into advanced techniques such as manipulating time in data-flow, customizing operators and providers, and exploring functional reactive programming. By the end of the book, you'll know how to apply reactive programming to solve complex problems and build efficient programs with reactive user interfaces.
Table of Contents (15 chapters)
Reactive Programming for .NET Developers
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface

Filtering events


As said in the previous section, it is time to alter message flow.

The observable interface has the task of producing messages, while conversely observer consumes such messages. To create a message filter, we need to create an object that is both a publisher and a subscriber together.

The implementation must take into consideration the filtering need and the message routing to underlying observers that subscribe to the filter observable object instead of the main one.

Here's an implementation of the filter:

/// <summary> 
/// The filtering observable/observer 
/// </summary> 
public sealed class StringMessageFilter : IObservable<string>, IObserver<string>, IDisposable 
{ 
    private readonly string filter; 
    public StringMessageFilter(string filter) 
    { 
        this.filter = filter; 
    } 
 
    //the observer collection 
    private readonly List<IObserver<string>> observerList...