Lua里实现将table转成字符串(序列化)和将字符串转换回table（反

转载自: http://www.voidcn.com/article/p-hhamkjgx-bcy.html

--[[ 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 .. ","
            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)
    if "{" == charTemp then
        m_szText = string.sub(m_szText,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)
            if "[" == charTemp or "=" == charTemp then
                stackOperator.pushBack(charTemp)
                m_szText = string.sub(m_szText,dLen)
            elseif '"' == charTemp then
                local s,e = string.find(m_szText,dLen)
                if nil ~= s and nil ~= e then
                    val = val .. string.sub(m_szText,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,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,dLen)
                else
                    return nil
                end
            elseif "{" == charTemp then
                m_szText = string.sub(m_szText,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,string.len(m_szText))
                return tRet
            elseif " " ~= charTemp then
                val = val .. charTemp
                m_szText = string.sub(m_szText,dLen)
            else
                m_szText = string.sub(m_szText,dLen)
            end
        end
        return tRet
    end
    local t = doS2T()
    return t
end

--[[ t = {1,2,3,"sdf",a = "df",qe = 3,{7},qq = {{2,a={}}},} t.f = {1,3} 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"] = {1,3}}
local sz = serialize(data)
print(sz)
print("---------")
print(serialize(unserialize(sz)))