In Written Test : They will give a problem and ask to write a solution using data structure and OOPS concept.Will definitely ask to measure the complexity of your program. In interviews : They will ask question from your program first(like used data structure, complexity, if any specific design pattern you used there etc etc) Then they will move to know your analytical skill mainly asking some small small problems. Question on data structure and design pattern will also be asked. How you have handled unmanaged code and how you take care of the garbage collection part etc. Some technology specific questions also may be asked .Question on web service, rest and soap api also may be asked.
Sigiloso
Take preparation on your technology , data structure and algorithm , design pattern , OOPS.