string.IsNullOrEmpty() vs string.NotNullOrEmpty()

Question

I\'m curious if any developers use string.IsNullOrEmpty() more often with a negative than with a positive

e.g.

if (!string.IsNullOrEmpty())

Answer 1

For those logicians out there, !string.IsNullOrEmpty is not equivalent to string.IsNotNullOrEmpty. @Guffa has it correct. Using DeMorgan's law, it would have to be string.IsNotNullAndNotEmpty to be equivalent.

¬(null ∨ empty) ⇔ ¬null ∧ ¬empty

¬(null ∨ empty) ≠ ¬null ∨ empty

The point here, I guess, is that the way it is currently is unambiguous, where as making the opposite unambiguous would be cumbersome.