In our SERVICE we will have 2 Interfaces:


The first Interface will be Implemented in Service.cs as the WCF service to make Server side operations like:
Register, Login, logout and Add Friend.

for Example:



Ths second Interface will be Implemented in the client form as a callback mehods which will be used by server to make changes in form's data to represent changes in server side.

for example:


This Application Full Source can be downloaded from this link:
Download

To Test this application you need first to import application MSSQL named: ChatDB.mdf in the attached file and run the server project then run the client to test it.