Limit Of Entered Characters ?

[Woovie]

I am trying to make a temporary nick system, similiar to Halo 3's tags.

I want it to be forced to be 1 letter, a-z, and 2 numbers, 0-9. How can I limit this ? Here is my code so far.

function joinRed ( player, commandName, shortName ) 
local nickCurrent = getClientName ( player ) 
local nickNew = shortName 
local nickSet = getElementData( thePlayer, "origNick" ) 
    if ( nickSet == false ) then 
        setElementData ( player, "origNick", nickCurrent ) 
    end 
setClientName ( player, nickNew ) 
end 

[Ace_Gambit]

I think what you are looking for is something called regular expressions or pattern matching. Lua has a few functions for pattern matching but I never tried them myself. You'll have to experiment with string.find, string.gfind and string.gsub.