Yet another guard clause project for .Net C#'ers
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Ensure.That is a simple guard clause argument validation lib, that helps you with validation of your arguments.

It's developed for .NET 4.5.1 as well as .NET Standard 1.1 and .NET Standard 2.0 and available via NuGet.

Using extension methods

This was supposed to be removed but after some wishes from the community it has been kept it with some slight changes.

If you are worried that the constructed public struct Param<T> {} created for the argument being validated will hurt your performance you can use any of the other constructs e.g. contextual Ensure.String or EnsureArg.

Ensure.That(myString, nameof(myArg)).IsNotNullOrWhiteSpace();
Ensure.That(myString, nameof(myArg), opts => opts.WithMessage("Foo")).IsNotNullOrWhiteSpace();

Using contextual validation

This flavour was introduced in the v7.0.0 release.

Ensure.String.IsNotNullOrWhiteSpace(myString, nameof(myArg));
Ensure.String.IsNotNullOrWhiteSpace(myString, nameof(myArg), opts => opts.WithMessage("Foo"));

Using static simple methods

The EnsureArg flavour was added in the v5.0.0 release.

EnsureArg.IsNotNullOrWhiteSpace(myString, nameof(myArg));
EnsureArg.IsNotNullOrWhiteSpace(myString, nameof(myArg), opts => opts.WithMessage("Foo"));


The Samples above just uses string validation, but there are more. E.g.:

  • Strings
  • Numerics
  • Collections (arrays, lists, collections, dictionaries)
  • Booleans
  • Guids

Get up and running with the source code

The main solution is maintained using Visual Studio 2017.

Unit-tests are written using xUnit and there are no integration tests, hence you should just be able to: Pull-Compile&Run the tests:

dotnet test