Question

I am currently developing a C# Windows Form Application that I intend to let it interact with a server. The server will receive posting from a mobile application that I have developed and whenever a posting is received, my Windows Form Application should be notified and give me a notification.

E.g. My mobile application sends an posting over to my server. Once my server receives the message, my windows form application should display a new notification showing the content of the message received and updates the UI accordingly.

In this type of scenario, it is better to use duplex WCF service or the just the regular WCF service?

If duplex, mind explaining why do I need to use duplex service? Thanks!

Answer 1

A duplex service is a service where two channels are created.

• The first channel is the ordinary client -> server channel using your service contract. This is what you’ll find in every WCF service, and is how your client can send a request to the service and it can respond.
• The second channel is a server -> client channel using a different service contract that you define. This second channel is how the server can send messages to the client without the client requesting them.

In your scenario, you seem to indicate that an event taking place on the server should send a message to your client. If this is the case, then yes, you need a duplex service so that the second channel exists, which allows the server to notify your client without the client initiating a request.