xUnit.net is a free, open source, community-focused unit testing tool for the .NET Framework.
Should testing for .NET - the way Asserting *Should* be!
Easy integration testing helper for ASP.Net Core applications
NUnit 3 Framework
Fluent API for asserting the results of unit tests that targets .NET Framework 4.5, 4.7, .NET Standard 1.3, 1.6 and 2.0. Supports the unit test frameworks MSTest, MSTest2, Gallio, NUnit, XUnit, MBunit, MSpec, and NSpec.
Modern Testing for .NET
.NET version of Pact. Enables consumer driven contract testing, providing a mock service and DSL for the consumer project, and interaction playback and verification for the service provider project.
Samples for xUnit.net (please open issues in https://github.com/xunit/xunit)