C#,asp.net import Excel, time format a series of numeric conversions.

In Excel. The date or time format is: 42093.6506944444 or 0.650694444444444

Greater than 0 indicates a date (2015-03-30), less than 0 is the time (15:37)

When the C # import reads this column, the conversion error occurs;

Now convert this format to the normal date format:

1 /// <summary>2     ///Digital Conversion Time format3     /// </summary>4     /// <param name= "Timestr" >numbers, such as: 42095.7069444444/0.650694444444444</param>5     /// <returns>Date/Time format</returns>6     Private stringTodatetimevalue (stringstrnumber)7     {8         if(!string. Isnullorwhitespace (strnumber))9         {Ten Decimal Tempvalue; One             //first check is not the number; A             if(Decimal.tryparse (Strnumber, outtempvalue)) -             { -                 //days, rounding the                 intDay =Convert.ToInt32 (Math.truncate (Tempvalue)); -                 //and I don't know why. Minus 1 if it's less than 32, or minus 2. -                 //Date starting from 1900-01-01 cumulative -                 //Day = Day < day-1: day-2; +DateTime dt =NewDateTime (1900,1,1). AddDays (Day < +? (Day-1): (Day-2)); -  +                 //hours: Minus the number of days, this number converted hours: (*) ADecimal hourtemp = (tempvalue-day) * -;//gets the number of hours at                 //Rounding . Number of hours -                 inthour =Convert.ToInt32 (Math.truncate (hourtemp)); -                 //minutes: Lose Hours, (*) -                 //rounding here, otherwise the value will have a 1 minute error. -Decimal minutetemp = Math.Round ((hourtemp-hour) * -,2);//gets the number of minutes -                 intminute =Convert.ToInt32 (Math.truncate (minutetemp)); in                 //seconds: Lose minutes, (*) -                 //rounding here, otherwise the value will have a 1 second error. toDecimal secondtemp = Math.Round ((minutetemp-minute) * -,2);//gets the number of seconds +                 intSecond =Convert.ToInt32 (Math.truncate (secondtemp)); -  the                 //time format: 00:00:00 *                 stringResulttimes =string. Format ("{0}:{1}:{2}", $(Hour <Ten? ("0"+hour): hour. ToString ()),Panax Notoginseng(Minute <Ten? ("0"+minute): minute. ToString ()), -(Second <Ten? ("0"+second): second. ToString ())); the  +                 if(Day >0) A                     return string. Format ("{0} {1}"Dt. ToString ("YYYY-MM-DD"), resulttimes); the                 Else +                     returnResulttimes; -             } $         } $         return string. Empty; -}

C#,asp.net import Excel, time format a series of numeric conversions.