// Example 1: Arranging the behavior of a setter property that returns void var mock = new MockMock ArrangeSet is typically used with a mocking framework such as Moq or Rhino Mocks. Therefore, it is part of the package/library for the specific mocking framework being used.(); mock.SetupSet(x => x.Property = It.IsAny ()); // Example 2: Arranging the behavior of a setter property to throw an exception var mock = new Mock (); mock.SetupSet(x => x.Property).Throws (); // Example 3: Arranging the behavior of a setter property to call a delegate var mock = new Mock (); mock.SetupSet(x => x.Property = It.IsAny ()).Callback ((val) => Console.WriteLine(val)); // Example 4: Arranging multiple setter properties at once var mock = new Mock (); mock.SetupSet(x => { x.Property1 = It.IsAny (); x.Property2 = It.IsAny (); });