You can interact with Facebook in C# by installing Facebook C# SDK dlls. The easiest way to do this is using NuGet. To add the reference, right click on “References”, and then click “Add Library Package Reference…”. From the Add Library Package Reference dialog do a search for “Facebook”. After the install completes click “Close”.
NuGet will do a few things automatically for us there. First, references for Facebook and Newtonsoft.Json will be added to the project. Second, some settings will be added to the web.config file. You also need to set our application so that it runs on the same port every time. So lets set the app to run on port 8080.
To give more scale to your Facebook app, you need to publish your app to Windows Azure. You can use the following links for this purpose:
Lastly, you can use the following links for leveraging Facebook with C# and with Windows Azure:
Windows Azure SDK and Windows Azure Tools for Microsoft Visual Studio Prerequisite
Facebook C# SDK Prerequisite
Building a Facebook Marketing App on Azure
Writing your first Facebook application