Overview of common DateTime methods in C

DateTime.Now.ToShortTimeString()
DateTime dt = DateTime.Now;
dt.ToString();//2005-11-5 13:21:25
dt.ToFileTime().ToString(); //127756416859912816
dt.ToFileTimeUtc().ToString();//127756704859912816
dt.ToLocalTime().ToString();//2005-11-5 21:21:25
dt. ToLongDateString (.) ToString (); // November 5, 2005
dt.ToLongTimeString().ToString();//13:21:25
dt.ToOADate().ToString();//38661.5565508218
dt.ToShortDateString().ToString();//2005-11-5
dt.ToShortTimeString().ToString();//13:21
dt.ToUniversalTime().ToString();//2005-11-5 5:21:25
dt.Year.ToString();//2005
dt.Date.ToString();//2005-11-5 0:00:00
dt.DayOfWeek.ToString();//Saturday
dt.DayOfYear.ToString();//309
dt.Hour.ToString();//13
dt.Millisecond.ToString();//441
dt.Minute.ToString();//30
dt.Month.ToString();//11
dt.Second.ToString();//28
dt.Ticks.ToString();//632667942284412864
dt.TimeOfDay.ToString();//13:30:28.4412864
dt.ToString();//2005-11-5 13:47:04
dt.AddYears(1).ToString();//2006-11-5 13:47:04
dt.AddDays(1.1).ToString();//2005-11-6 16:11:04
dt.AddHours(1.1).ToString();//2005-11-5 14:53:04
dt.AddMilliseconds(1.1).ToString();//2005-11-5 13:47:04
dt.AddMonths(1).ToString();//2005-12-5 13:47:04
dt.AddSeconds(1.1).ToString();//2005-11-5 13:47:05
dt.AddMinutes(1.1).ToString();//2005-11-5 13:48:10
dt.AddTicks(1000).ToString();//2005-11-5 13:47:04
dt.CompareTo(dt).ToString();//0
dt. Add (?) ToString (); // question mark is 1 time period
dt.Equals("2005-11-6 16:11:04").ToString();//False
dt.Equals(dt).ToString();//True
dt.GetHashCode().ToString();//1474088234
dt.GetType().ToString();//System.DateTime
dt.GetTypeCode().ToString();//DateTime

dt.GetDateTimeFormats('s')[0].ToString();//2005-11-05T14:06:25
dt.GetDateTimeFormats('t')[0].ToString();//14:06
dt. GetDateTimeFormats (' y) [0]. ToString (); / / in November 2005
dt. GetDateTimeFormats (' D) [0]. ToString (); // November 5, 2005
dt.GetDateTimeFormats('D')[1].ToString();//2005 11 05
dt. GetDateTimeFormats (' D) [2]. ToString (); // Monday 6, 2005 11, 05
dt. GetDateTimeFormats (' D) [3]. ToString (); // Monday 6 November 5, 2005
dt. GetDateTimeFormats (' M) [0]. ToString (); / / on November 5
dt. GetDateTimeFormats (' f) [0]. ToString (); // on November 5, 2005, 14:06
dt.GetDateTimeFormats('g')[0].ToString();//2005-11-5 14:06
dt.GetDateTimeFormats('r')[0].ToString();//Sat, 05 Nov 2005 14:06:25 GMT
string.Format("{0:d}",dt);//2005-11-5
string. Format (" {0: D} ", dt); // November 5, 2005
string. Format (" {0: f} ", dt); // November 5, 2005 14:23
string. Format (" {0: F} ", dt); // November 5, 2005 14:23:23
string.Format("{0:g}",dt);//2005-11-5 14:23
string.Format("{0:G}",dt);//2005-11-5 14:23:23
string. Format (" {0: M} ", dt); / / on November 5
string.Format("{0:R}",dt);//Sat, 05 Nov 2005 14:23:23 GMT
string.Format("{0:s}",dt);//2005-11-05T14:23:23
string.Format("{0:t}",dt);//14:23
string.Format("{0:T}",dt);//14:23:23
string.Format("{0:u}",dt);//2005-11-05 14:23:23Z
string. Format (" {0: U} ", dt); // November 5, 2005 6:23:23
string. Format (" {0: Y} ", dt); / / in November 2005
string.Format("{0}",dt);//2005-11-5 14:23:23
string.Format("{0:yyyyMMddHHmmssffff}",dt);
Calculate the number of days between the two dates
-----------------------------------------------
DateTime dt1 = Convert.DateTime("2007-8-1");
DateTime dt2 = Convert.DateTime("2007-8-15");
TimeSpan span = dt2.Subtract(dt1);
int dayDiff = span.Days + 1;
Count the number of days in a year
-----------------------------------------------
int days = DateTime.DaysInMonth(2007, 8);
days = 31;
Add one day to the date and subtract one day from it
-----------------------------------------------
DateTime dt =DateTime.Now;
dt. AddDays (1); // add one more day
dt. AddDays (1); // one less day
Other year methods are similar...
Convert the date function in Oracle SQL
-----------------------------------------------
to_date("2007-6-6",'YYYY-MM-DD");
to_date("2007/6/6",'yyyy/mm/dd");
The following is a set of data. How to find the records of September in the table:
CGGC_STRATDATE CGGC_ENDDATE
=========================================
2007-8-4 2007-9-5
2007-9-5 2007-9-20
2007-9-22 2007-10-5
SELECT * FROM TABLE
(TO_DATE('2007/9/1','yyyy/mm/dd') BETWEEN CGGC_STRATDATE
AND CGGC_ENDDATE OR CGGC_STRATDATE > =TO_DATE('2007/9/1','yyyy/mm/dd')
AND CGGC_ENDDATE < =TO_DATE('2007/9/30','yyyy/mm/dd') "
OR TO_DATE('2007/9/30','yyyy/mm/dd') BETWEEN CGGC_STRATDATE
AND CGGC_ENDDATE) ORDER BY CGGC_STRATDATE ASC