C# Use DateTime.ParseExact() instead of DateTime.Parse()

I didn’t notice this until today, the DateTime I retrieve from my database has the format of yyyy/MM/dd hh:mm:ss.fff

and if I use DateTime.Parse(), the .fff value will be lost.

After searching google, I find out that not only DateTime.Parse() has this one problem, it also has problem with culture setting.

So, whenever you what to parse a DateTime, use DateTime.ParseExact().

Here is an useful example :

string[] DateTimeList = {
                            "yyyy/M/d tt hh:mm:ss",
                            "yyyy/MM/dd tt hh:mm:ss",
                            "yyyy/MM/dd HH:mm:ss",
                            "yyyy/M/d HH:mm:ss",
                            "yyyy/M/d",
                            "yyyy/MM/dd"
                        }; 
DateTime dt = DateTime.ParseExact(" 2008/  3/18   PM 02: 50:23  ",
                                                 DateTimeList,CultureInfo.InvariantCulture,
                                                 DateTimeStyles.AllowWhiteSpaces
                                  );

Remember, CultureInfo is important to parsing, for example tt in Chinese will be 上午/下午, in en-US will be AM/PM. You can use CultureInfo.CreateSpecificCulture() to create the culture you need.
A small pattern reference

yyyy year ‘2009’
MM month ’04’
dd day ’17’
HH 24 hour ’23’
hh 12 hour ’11’
mm minutes ’59’
ss seconds ’30’
tt AM/PM
zzz GMT

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