Lua里实现将table转成字符串(序列化)和将字符串转换回table（反序列化）

 --[[
  file name :    table序列化和反序列化的问题.lua
  author  :      Clark/陈泽丹
  created :      2011-12-22
  备注：
  支持table的递归结构，但数据类型不支持function属性(因为function只是记录地址，在不同机器上序列化和反序列化后的地址相同没什么意义)

  后记:
  郁闷， 写完到网上一搜， 才发现原来Lua有提供一些现成的函数可用来做序列化和反序列化操作。。。
  其中loadstring可以执行字符串。
  通过
  lua = "return " .. lua
  local func = loadstring(lua)
  即实现了反序列化。。。
 --]]



 ----------- 个人编写 -----------------

 --table转字符串(只取标准写法，以防止因系统的遍历次序导致ID乱序)
 function sz_T2S(_t)
     local szRet = "{"
     function doT2S(_i, _v)
         if "number" == type(_i) then
             szRet = szRet .. "[" .. _i .. "] = "
             if "number" == type(_v) then
                 szRet = szRet .. _v .. ","
             elseif "string" == type(_v) then
                 szRet = szRet .. '"' .. _v .. '"' .. ","
             elseif "table" == type(_v) then
                 szRet = szRet .. sz_T2S(_v) .. ","
             else
                 szRet = szRet .. "nil,"
             end
         elseif "string" == type(_i) then
             szRet = szRet .. '["' .. _i .. '"] = '
             if "number" == type(_v) then
                 szRet = szRet .. _v .. ","
             elseif "string" == type(_v) then
                 szRet = szRet .. '"' .. _v .. '"' .. ","
             elseif "table" == type(_v) then
                 szRet = szRet .. sz_T2S(_v) .. ","
             else
                 szRet = szRet .. "nil,"
             end
         end
     end
     table.foreach(_t, doT2S)
     szRet = szRet .. "}"
     return szRet
 end



 --字符串转table(反序列化,异常数据直接返回nil)
 function t_S2T(_szText)
     --栈
     function stack_newStack()
         local first = 1
         local last = 0
         local stack = {}
         local m_public = {}
         function m_public.pushBack(_tempObj)
             last = last + 1
             stack[last] = _tempObj
         end
         function m_public.temp_getBack()
             if m_public.bool_isEmpty() then
                 return nil
             else
                 local val = stack[last]
                 return val
             end
         end
         function m_public.popBack()
             stack[last] = nil
             last = last - 1
         end
         function m_public.bool_isEmpty()
             if first > last then
                 first = 1
                 last = 0
                 return true
             else
                 return false
             end
         end
         function m_public.clear()
             while false == m_public.bool_isEmpty() do
                 stack.popFront()
             end
         end
         return m_public
     end
     function getVal(_szVal)
         local s, e = string.find(_szVal,'"',1,string.len(_szVal))
         if nil ~= s and nil ~= e then
             --return _szVal
             return string.sub(_szVal,2,string.len(_szVal)-1)
         else
             return tonumber(_szVal)
         end
     end

     local m_szText = _szText
     local charTemp = string.sub(m_szText,1,1)
     if "{" == charTemp then
         m_szText = string.sub(m_szText,2,string.len(m_szText))
     end
     function doS2T()
         local tRet = {}
         local tTemp = nil
         local stackOperator = stack_newStack()
         local stackItem = stack_newStack()
         local val = ""
         while true do
             local dLen = string.len(m_szText)
             if dLen <= 0 then
                 break
             end

             charTemp = string.sub(m_szText,1,1)
             if "[" == charTemp or "=" == charTemp then
                 stackOperator.pushBack(charTemp)
                 m_szText = string.sub(m_szText,2,dLen)
             elseif '"' == charTemp then
                 local s, e = string.find(m_szText, '"', 2, dLen)
                 if nil ~= s and nil ~= e then
                     val = val .. string.sub(m_szText,1,s)
                     m_szText = string.sub(m_szText,s+1,dLen)
                 else
                     return nil
                 end
             elseif "]" == charTemp then
                 if "[" == stackOperator.temp_getBack() then
                     stackOperator.popBack()
                     stackItem.pushBack(val)
                     val = ""
                     m_szText = string.sub(m_szText,2,dLen)
                 else
                     return nil
                 end
             elseif "," == charTemp then
                 if "=" == stackOperator.temp_getBack() then
                     stackOperator.popBack()
                     local Item = stackItem.temp_getBack()
                     Item = getVal(Item)
                     stackItem.popBack()
                     if nil ~= tTemp then
                         tRet[Item] = tTemp
                         tTemp = nil
                     else
                         tRet[Item] = getVal(val)
                     end
                     val = ""
                     m_szText = string.sub(m_szText,2,dLen)
                 else
                     return nil
                 end
             elseif "{" == charTemp then
                 m_szText = string.sub(m_szText,2,string.len(m_szText))
                 local t = doS2T()
                 if nil ~= t then
                     szText = sz_T2S(t)
                     tTemp = t
                     --val = val .. szText
                 else
                     return nil
                 end
             elseif "}" == charTemp then
                 m_szText = string.sub(m_szText,2,string.len(m_szText))
                 return tRet
             elseif " " ~= charTemp then
                 val = val .. charTemp
                 m_szText = string.sub(m_szText,2,dLen)
             else
                 m_szText = string.sub(m_szText,2,dLen)
             end
         end
         return tRet
     end
     local t = doS2T()
     return t
 end

 --[[
 t = {1,2,3,"sdf", a = "df", qe = 3, {7}, qq = {{2,3,a={}}}, }
 t.f = {1,2,3}
 t.m = {3,4,5}
 szT = sz_T2S(t)
 print(szT)
 print("-----------")
 tq = t_S2T(szT)
 szT = sz_T2S(tq)
 print(szT)
 --]]


 -------- 网上资料 -------------------



 function serialize(obj)
     local lua = ""
     local t = type(obj)
     if t == "number" then
         lua = lua .. obj
     elseif t == "boolean" then
         lua = lua .. tostring(obj)
     elseif t == "string" then
         lua = lua .. string.format("%q", obj)
     elseif t == "table" then
         lua = lua .. "{\n"
     for k, v in pairs(obj) do
         lua = lua .. "[" .. serialize(k) .. "]=" .. serialize(v) .. ",\n"
     end
     local metatable = getmetatable(obj)
         if metatable ~= nil and type(metatable.__index) == "table" then
         for k, v in pairs(metatable.__index) do
             lua = lua .. "[" .. serialize(k) .. "]=" .. serialize(v) .. ",\n"
         end
     end
         lua = lua .. "}"
     elseif t == "nil" then
         return nil
     else
         error("can not serialize a " .. t .. " type.")
     end
     return lua
 end

 function unserialize(lua)
     local t = type(lua)
     if t == "nil" or lua == "" then
         return nil
     elseif t == "number" or t == "string" or t == "boolean" then
         lua = tostring(lua)
     else
         error("can not unserialize a " .. t .. " type.")
     end
     lua = "return " .. lua
     local func = loadstring(lua)
     if func == nil then
         return nil
     end
     return func()
 end

 data = {["a"] = "a", ["b"] = "b", [1] = 1, [2] = 2, ["t"] = {1, 2, 3}}
 local sz = serialize(data)
 print(sz)
 print("---------")
 print(serialize(unserialize(sz)))