title: C# Interface for multiple classes
body: <p>I have a data provider project to access the database. this is composed by various classes (PersonDataProvider, JobDataProvider ...) 
  I want to create an Interface.
  Do I have to create an Interface for each class?
  I was tempted to create one interface and than inherit on all the classes. This involves making all the projects classes partial and change the classes name.......But i think is not the best solution.
  Any suggestion?</p>