When to use a Mocking Framework?

Question

So I am playing around with mocking frameworks (Moq) for my unit tests, and was wondering when you should use a mocking framework?

What is the benefit/disadvantage b

Answer 1

Mock is used to test object that cannot function in isolation. suppose function A is dependent on function B, to perform unit testing on function A we even end up testing function B.By using mock you can simulate the functionality of function B and testing can be focussed only on function A.