Empty readonly Action delegate

Question

There are a number of places in our code where () => {} is used (required Action parameter in methods of third-party library).
To make code cleaner I created the following class:

public static class Empty
{
    public static readonly Action Action = () => {};
}

Now it is much nicer:

Alert.Show(title, message, Empty.Action);

The question is may this refactoring cause any problems? I'm sure no but you may know possible side cases. Or may be you know better code improvement here?

Answer 1

This change is technically observable: there is always the possibility that some code indirectly compares two new Action(() => {}) instances for equality, and where they would previously not compare equal, they do now.

For an example, if you expose an public event Action X;, you might make sure to initialise it to () => {} to make sure it's never null, and remove any null checks from your code. If you change this to Empty.Action, then malicious code could write X -= Empty.Action;, causing a NullReferenceException in your own code where the event gets invoked.

But in well-written code, the refactoring should not make any difference.

Answer 2

This will not cause any problems, as it is equivalent to defining a static method and referencing it multiple times in your assembly