I have a collection call colCustomers with a key element CustomerID. CustomerID is in the sequence 0001, 0002, 0003 etc... However sometimes a key may be skipped eg: 0001, 0002, 0004, 0005, 0006. I need to be able to find out what the last CustomerID is so that I can create a new one that is one number higher. I don't want to create in a missing spot and I don't want to resort the collection and change every CustomerID so non are skipped.