lua向文件中寫入數據，進行記錄

function readfile(path)
      local file = io.open(path, "r")
      if file then
        local content = file:read("*a")
        io.close(file)
        return content
      end
      return nil
end

function writefile(path, content, mode)
      mode = mode or "w+b"
      local file = io.open(path, mode)
      if file then
        if file:write(content) == nil then return false end
        io.close(file)
        return true
      else
        return false
      end
end
--文件讀寫測試
local a = {x=1,y=2,z=3}
local str = json.encode(a)                --將lua表編碼為json格式字符串
local path = cc.FileUtils:getInstance():getWritablePath()
    path = path..filename                 --得到可讀寫文件的路徑
    writefile(path,str,r)                 --將數據寫入文件
local b = readfile(path)                  --從文件中讀取數據
    printf(b)
end


2. 文件操作示例代碼
local path = cc.FileUtils:getInstance():getWritablePath()
cc.FileUtils:getInstance():writeToFile({key="value"}, paht.."filename")     --讀取數據的方式
print(ret.key) 
lcoal ret = cc.FileUtils:getInstance():getValueMapFromFile(Path.."filename")  --讀取數據的方式2
print(str)
local str = cc.FileUtils:getInstance():getStringFromFile(path.."filename")