How Can I Make Use Of Moq Framework To Mock My Repositories?

See more:

.NET

.NET4

MVC4

EF5.0

unit-testing

I'm able to create mock objects and do a update test with mocked entities successfully.
But the issue is with create test. Here is my sample code.
In this always my testPG is null and so the test fails

base class:

public class TestContext where T : class
   {

       protected Mock<t> mockRepository;
       protected Mock<testentities> mockTestEntities;

       protected TestContext()
       {
           mockRepository = new Mock<t>(MockBehavior.Strict);
           mockTestEntities= new Mock<testentities>(MockBehavior.Strict);
           mockTestEntities.Setup(ase => ase.SaveChanges()).Returns(1);
      }


public class PGRepositoryTest : TestContext<ipgrepository>
    {


 [TestInitialize]
        public void TestInitialize()
        {
            pgRepository = new PGRepository(mockTestEntities.Object);
                
          pgViewModel = new PGViewModel
                                {   ID = 1,
                                    Name = "PG Unit Test",
                                    DisplayName = "PG Unit Test",
                                    IsActive = true,                                    
                                };
            sessionViewModel = pgViewModel;

            userContext = new UserContext
                                {
                                    UserID = "XXXX"
                                };
}


 [TestMethod]
        public void CreateTest()
        {
            
            var IdSet = new IDSet();
            
            IdSet = pgRepository.Create(pgViewModel, sessionViewModel, userContext);
            
            PresentationGroupViewModel testPG = pgRepository.GetPresentationGroup(IdSet.ID);              

              Assert.AreEqual(IdSet.ID, testPG.ID);

        }
}</ipgrepository></testentities></t></testentities></t>