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VB/OLE DATE conversion in .NET CF 1.0

For a  .NET CF 1.0 program I'm working I have to use a VB/OLE Automation DATE from C#. The .NET methods FromOADate and ToOADate are not available on .NET CF 1.0 so I ported the VB.NET implementation of FromOADate and ToOADate to C#

 

 

public static System.DateTime OleDateToDateTime(double date)

{

      const Int32 hex1 = 86400000;              //0x5265c00

      const Int64 hex2 = 59926435200000;        //0x3680b5e1fc00

      const Int64 hex3 = 315537897600000;       //0x11efae44cb400

      const Int32 hex4 = 10000;                       //0x2710

      const double real1 = 86400000;     

      const double real2 = 2958466;

      const double real3 = -657435;

     

      if (date >= real2 || date <= real3)

      {

            throw new ArgumentException("Arg_OleAutDateInvalid");

      }

 

      double toAdd = date >= 0 ? 0.5 : -0.5;

 

      long loc0 = (long) (date * real1 + toAdd);

      if (loc0 < 0)

      {    

            loc0 -= (2 * getReminder(loc0, hex1));

      }

      loc0 += hex2;

     

      if (loc0 < 0 || loc0 >= hex3)

      {

            throw new ArgumentException("Arg_OleAutDateScale");

      }

 

      return new DateTime(loc0 * hex4);        

}

 

public static double DateTimeToOleDate(System.DateTime date)

{

      const Int32 hex1 = 86400000;              // '0x5265c00

      const Int64 hex2 = 599264352000000000;    // '0x85103c0cb83c000

      const Int64 hex3 = 31241376000000000;     // '0x6efdddaec64000

      const Int32 hex4 = 10000;                       // '0x2710

      const Int64 hex5 = 864000000000;          // '0xc92a69c000

      const double real1 = 86400000;     

 

      long ticks = date.Ticks;

 

      if (0 == ticks)

      {

            return 0.0;

      }

     

      if (ticks < hex5)

      {

            ticks += hex2;

      }

 

      if (ticks < hex3)            

      {

            throw new ArgumentException("Arg_OleAutDateInvalid");

      }

 

      long loc1;

      long loc0 = (long) ((ticks - hex2) / hex4);

 

      if (loc0 < 0)

      {

            loc1 = getReminder(loc0, hex1);

            if (0 != loc1)

            {

                  loc0 -= (hex1 + loc1) * (2);

            }                

      }

     

      return ((double) loc0) / real1;

}

 

 

private static long getReminder(long value1, long value2)

{

      long res;

      res = value1 - value2 * (value1 / value2); 

      return res;      

}