Yet another guard clause project for .Net C#'ers
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Latest commit 2c0d1f0 Oct 9, 2016 @danielwertheim committed on GitHub Link to NuGet


Ensure.That is a simple guard clause argument validation lib, that helps you with validation of your arguments.


Ensure.That is distributed via NuGet and since v5.0.0 it's being built using DotNetCore and targes the frameworks:

  • .NetStandard1.1
  • .Net4.5+
install-package Ensure.That

Samples (two different APIs)

Samples below just list one validation method, but the API contains validation methods for e.g.:

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

Using static simple methods

This flavour was added in the v5.0.0 release and this is my prefered way, because it has less overhead (read more below).

EnsureArg.IsNotNullOrWhiteSpace(myString, nameof(myArg));

Using extension methods

This is the initial way of doing validation, but this IS NOT my prefered way. Why? Well because it will create a new instance of Param<T> wrapping the value being passed, so that the context-aware extension methods can target correct type.

Ensure.That(myString, nameof(myArg)).IsNotNullOrWhiteSpace();
    .That(myString, nameof(myString))
    .WithExtraMessageOf(p => "Some more details")
    .That(myString, nameof(myString))
    .WithException(param => new Exception())

Turn On/Off - default is On

Could be used with different profiles. Like Debug and CI is On while Release is Off.


Release notes

Available from v2.0.0,

Get up and running with the source code

The main solution is maintained using Visual Studio 2015.

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

Issues, questions, etc.

So you have issues or questions... Great! That means someone is using it. Use the issues function here at the project page or contact me via mail:; or Twitter: @danielwertheim