PHP if not statements

Question

This may be the way my server is set up, but I\'m banging my head against the wall. I\'m trying to say that if $action has no value or has a value that is not \

Answer 1

You're saying "if it's not set or it's different from add or it's different from delete". You realize that a != x && a != y, with x != y is necessarily false since a cannot be simultaneously two different values.