Mastering Unit Testing in .NET with Moq: 10 Essential Examples for Mocking Dependencies

Mocking is a critical technique in unit testing, enabling developers to isolate the code under test by simulating the behavior of dependencies. Moq, a popular mocking library in .NET, provides an intuitive and powerful API for creating mock objects, allowing for precise control over method behaviors and interactions. This ensures that your tests remain focused, reliable, and independent of external dependencies.

In this article, we’ll explore 10 practical examples of using Moq in a .NET environment, covering a range of scenarios from basic method mocking and verification to handling more advanced cases like asynchronous methods and callbacks. These examples are designed to demonstrate how Moq can be used to test various aspects of your code effectively.

We’ll start with the basics: creating mock objects and verifying method calls with specific arguments. These foundational techniques are essential for understanding more complex scenarios. From there, we’ll move on to advanced features, such as mocking properties, handling exceptions, and working with methods that return sequences of values.

Moq also excels at verifying that certain methods or properties were accessed as expected, which is crucial when your code interacts with external services or…