I am convinced that this requirement is so simple it's embarrassing to ask but for some reason it is escaping me, perhaps I don't know enough about Regular Expressions. :)
All I need to do is validate a string which needs to match 1-4 numbers followed optionally by a single letter (upper or lower case a-z). so 9, 8a, 225z are all valid but, a, 2ab, 12345a, are invalid.
All help very welcome!
ps I have no idea what I'm wanted to enter under "Tags" so I just picked one at random!