Ensure.That

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

Developed for: .NET4.6.2, .NET5.0, .NET Standard 2.0 and 2.1 available via NuGet.

Ensure.That - Using extension methods

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

Chainable:

Ensure
.That(myString)
.IsNotNullOrWhiteSpace()
.IsGuid();

Easily extendable:

public static class StringArgExtensions
{
    public static StringParam IsNotFishy(this StringParam param)
        => param.Value != "fishy"
            ? param
            : throw Ensure.ExceptionFactory.ArgumentException("Something is fishy!", param.Name);
}

Ensure.That(myString, nameof(myString)).IsNotFishy();

NOTE: If you are worried that the constructed public readonly 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 (see below for samples).

Ensure.Context - Using contextual validation

Introduced in the v7.0.0 release.

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

Easily extendable:

public static class StringArgExtensions
{
    public static string IsNotFishy(this StringArg _, string value, string paramName = null)
        => value != "fishy"
            ? value
            : throw Ensure.ExceptionFactory.ArgumentException("Something is fishy!", paramName);
}

Ensure.String.IsNotFishy(myString, nameof(myString));

EnsureArg - Using simple static methods

Introduced in the v5.0.0 release.

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

Easily extendable:

public static partial class EnsureArg
{
    public static string IsNotFishy(string value, string paramName = null)
        => value != "fishy"
            ? value
            : throw Ensure.ExceptionFactory.ArgumentException("Something is fishy!", paramName);
}

EnsureArg.IsNotFishy(myString, nameof(myString));