EnsureArg (nuget): A lightweight and extensible guard clause library.   Example: Ensure.Arg(param1, "param1").IsNotNull();  The library is easily extensible through the use of extension methods. Even the main Ensure.Arg(...) call can be overridden to whatever you prefer e.g. Verify.That(...)  See the project site for many more examples
Keywords: argument|validation|guard|clause|ensure|ensurearg