Console.WriteLine(DateTime.ParseExact(20210511102323.ToString(), "yyyyMMddHHmmss", new CultureInfo("zh-CN", true),DateTimeStyles.AllowInnerWhite).ToString("yyyy-MM-dd HH:mm:ss"));
2021-07-18 02:32:08
Console.WriteLine(DateTime.ParseExact(20210511102323.ToString(), "yyyyMMddHHmmss", new CultureInfo("zh-CN", true),DateTimeStyles.AllowInnerWhite).ToString("yyyy-MM-dd HH:mm:ss"));