时间戳与时间相互转换(php .net精确到毫秒)

/** 获取当前时间戳，精确到毫秒 */
function microtime_float()
{
  list($usec, $sec) = explode(" ", microtime());
  return ((float)$usec + (float)$sec);
}
/** 格式化时间戳，精确到毫秒，x代表毫秒 */
function microtime_format($tag, $time)
{
  list($usec, $sec) = explode(".", $time);
  $date = date($tag,$usec);
  return str_replace('x', $sec, $date);
}

 /// <summary>
     /// Unix时间戳转换为DateTime
     /// </summary>
     private DateTime ConvertToDateTime(string timestamp)
     {
       System.DateTime time = System.DateTime.MinValue;
       //精确到毫秒
       //时间戳转成时间
       DateTime start = TimeZone.CurrentTimeZone.ToLocalTime(new System.DateTime(, , ));
       try
       {
         time = timestamp.Length == ? start.AddSeconds(long.Parse(timestamp)) : start.AddMilliseconds(long.Parse(timestamp));
       }
       catch (Exception ex)
       {
         return start;//转换失败
       }
       return time;
     }
     /// <summary>
     /// DateTime转换为Unix时间戳
     /// </summary>
     /// <param name="time"></param>
     /// <returns></returns>
     private string ConvertTimestamp(DateTime time)
     {
       double intResult = ;
       System.DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new System.DateTime(, , ));
       intResult = (time - startTime).TotalMilliseconds;
       return Math.Round(intResult,).ToString();
     }