/// <summary>

        /// 定期清除文件

        /// </summary>

        /// <param name="fileDirect">文件夹</param>

        /// <param name="postFix">文件后缀</param>

        /// <param name="saveDay">保存天数</param>

        private void DeleteFile(string fileDirect, string postFix, int saveDay)

        {

            DateTime nowtime = DateTime.Now; //获取当前时间

            string[] files = Directory.GetFiles(fileDirect, postFix, SearchOption.AllDirectories);  //获取该目录下所有 .txt文件

            foreach (string file in files)

            {

                FileInfo fileInfo = new FileInfo(file);

                TimeSpan t = nowtime - fileInfo.CreationTime;  //当前时间  减去 文件创建时间

                int day = t.Days;

                if (day > saveDay)   //保存的时间 ；  单位：天

                {

                    File.Delete(file);  //删除超过时间的文件

                }

            }

        }

 pathLast = @"\" + day + ".xls"; //文件名

            pathHeard = Ini.IniReadValue("配置文件", "path"); //文件夹

            path = pathHeard + pathLast; //文件路径

            string deleteDay = Ini.IniReadValue("清除文件", "day"); //定期删除文件天数

            int deleteDayValue = -1;

            switch (deleteDay)

            {

                case "4":

                    deleteDayValue = -1;

                    break;

                case "3":

                    deleteDayValue = 3;

                    break;

                case "2":

                    deleteDayValue = 7;

                    break;

                case "1":

                    deleteDayValue = 15;

                    break;

                case "0":

                    deleteDayValue = 30;

                    break;

                default:

                    break;

            }

            if (deleteDayValue >= 0)

            {

                DeleteFile(pathHeard, "*.xls", deleteDayValue);

            }