Admin commands? - so stumped

            if string.find(gui.TextBox.Text,"ff;") then
                --local pattern="^ff;%w+"
                local match=(gui.TextBox.Text):match("^ff;%w+")
                if match then
                    local var=string.lower(string.match(match,".+",4))
                    for _,v in pairs(game.Players:GetPlayers()) do
                        local player=string.lower(v.Name)
                        if var==string.sub(player,1,4)  then
                        local forcefield=Instance.new("ForceField", v.Character)
                        end
                    end
                    if string.match(gui.TextBox.Text,"^ff;me$") then
                    local forcefield=Instance.new("ForceField", Char)
                    end
                end
            end 

So I really want to improve on this, because it truly looks very ugly. But i'm usin it for now (I made it), anyways the problem is the fact that some players have ridiculously long names on purpose, for example: "JohnCenaLover59595959422", and let's say I want to forcefield them, instead of typing that out, can I just make it so I only have to say: ff;john

Thanks!