Throwing Custom exceptions

[lars-lindstrom]

I have previously used the Ardalis Specification/Repository assembly with great pleasure and currently the GuardClause assembly got my attention.
In general it is great and I love it. But listening to your podcasts, inspired me to use custom exceptions to a greater extend. Unfortunately I have fails to identify a way to either use functionality within Ardalis GuardClauses or to make and overloaded version myself.
What I’m looking for I something like this: Guard.Agains.Null(null object)

[ardalis]

I would use the extension approach shown in the project README. Don't just call it Guard.Against.Null() though but something more specific like Guard.Against.MissingOrder(Order order) so that it's more specific and obvious when the problem occurs (that's the point of my prefer custom exceptions advice).

https://ardalis.com/prefer-custom-exceptions-to-framework-exceptions/

Extending with your own Guard Clauses

To extend your own guards, you can do the following:

// Using the same namespace will make sure your code picks up your 
// extensions no matter where they are in your codebase.
namespace Ardalis.GuardClauses
{
    public static class FooGuard
    {
        public static void Foo(this IGuardClause guardClause, string input, string parameterName)
        {
            if (input?.ToLower() == "foo")
                throw new ArgumentException("Should not have been foo!", parameterName);
        }
    }
}

// Usage
public void SomeMethod(string something)
{
    Guard.Against.Foo(something, nameof(something));
}