我可以使用哪种格式的字符串来解析Oracle TIMESTAMP？

Question

I have the following value stored in an Oracle TIMESTAMP column 05-JAN-18 12.00.00.000000000 AM . I am trying to parse the values and convert them to something that is SQL Server DATETIME friendly. This is what I am trying to do:

DateTime result;
DateTime.TryParseExact(
    "05-JAN-18 12.00.00.000000000 AM",
    "dd-MMM-yy hh.mm.ss.fffffff tt", 
    new CultureInfo("en-US"), DateTimeStyles.None,
    out result))

except this is not working because the format string does not have the precision to parse all of the milliseconds. How can I get around this? Is there a different format string I can use, or a better way to convert Oracle TIMESTAMP to DateTime ?

Answer 1

For your modified question and data you need fffffff00 for millisecond part.

   DateTime result;
   DateTime.TryParseExact(
       "10-JAN-12 03.51.35.028000000 PM",
       "dd-MMM-yy hh.mm.ss.fffffff00 tt",
       new CultureInfo("en-US"), DateTimeStyles.None,
       out result);

For more see: Custom Date and Time Format Strings

Answer 2

In .NET, maximum number of significant digits of the seconds is seven which is represent as fffffff .

That's why you have to remove 00 part on your original string's fraction part if you want to parse successfully.

DateTime result;
DateTime.TryParseExact(
    "05-JAN-18 12.00.00.0000000 AM",
    "dd-MMM-yy hh.mm.ss.fffffff tt", 
    new CultureInfo("en-US"), DateTimeStyles.None,
    out result))

Or you can use string delimiter (if these two digits are always 00 ) like;

DateTime result;
DateTime.TryParseExact(
    "05-JAN-18 12.00.00.000000000 AM",
    "dd-MMM-yy hh.mm.ss.fffffff'00' tt", 
    new CultureInfo("en-US"), DateTimeStyles.None,
    out result))