【德州扑克开发记录】lua提取字符串中的中英文

local tb = {}
local lenInByte = #str
local i = 1
while i < (lenInByte + 1) do
   local curByte = string.byte(str, i)
   local szType
   local byteCount=1
   if curByte>0 and curByte<=127 then
      if curByte>=48 and curByte<=57 then
         szType = 'num'
      elseif (curByte>=97 and curByte<=122) or
            (curByte>=65 and curByte<=90) then
         szType = 'letter'
      end
      byteCount = 1
   elseif curByte>=192 and curByte<223 then
      byteCount = 2
   elseif curByte>=224 and curByte<239 then
      byteCount = 3
   elseif curByte>=240 and curByte<=247 then
      byteCount = 4
   end

   local char = string.sub(str, i, i+byteCount-1)
   i = i + byteCount

   local item = {}
   if byteCount == 1 then
      item.type = szType and szType or "en"
   else
      item.type = "cn"
   end

   item.value = char

   table.insert(tb, item)
end