[Jay_]

You're getting confused with GetPlayerKeys and OnPlayerKeyStateChange. GetPlayerKeys simply returns the current keys the player is pressing, whereas the OnPlayerKeyStateChange callback is called every time a player changes their key combination. It wouldn't make sense to include an oldkeys parameter in this function.

I don't know why you would favor GetPlayerKeys over OnPlayerKeyStateChange for this functionality. But nonetheless, you'd have to store their previous "oldkeys" attribute in variables which you can compare and retrieve when getting their new keys.