Method to Convert C# String Date-Time String to DateTime Type

Method one: Convert.ToDateTime(string)

The string format has requirements, it must be yyyy-MM-dd hh:mm:ss

Method two: Convert.ToDateTime(string, IFormatProvider)

DateTime dt;
DateTimeFormatInfo dtFormat = new System.Globalization.DateTimeFormatInfo();
dtFormat.ShortDatePattern = "yyyy/MM/dd";
dt = Convert.ToDateTime("2011/05/26", dtFormat);

Method three: DateTime.ParseExact()

string dateString = "20110526";
DateTime dt = DateTime.ParseExact(dateString, "yyyyMMdd", System.Globalization.CultureInfo.CurrentCulture);

or

DateTime dt = DateTime.ParseExact(dateString, "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture);

Append reference information:

CultureInfo cultureInfo = CultureInfo.CreateSpecificCulture("en-US");-US
string format = "ddd MMM d HH:mm:ss '00' yyyy";
string stringValue = DateTime.Now.ToString(format, cultureInfo); // Get the date string
DateTime datetime = DateTime.ParseExact("Wed Aug", 25 16:28:03 +0800 2010", format, cultureInfo); // Convert a string to a date

Others

Date format: yyyyMMdd HH:mm:ss (note that the case of the string is very strict)
yyyy: represents years
MM: represents months
dd: represents days
HH: represents hours (2412-hour format)
mm: represents minutes
ss: represents seconds
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();//2005Year11Month5Day
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();//a question mark represents a 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();//2005Year11Month
dt.GetDateTimeFormats('D')[0].ToString();//2005Year11Month5Day
dt.GetDateTimeFormats('D')[1].ToString();//2005 11 05
dt.GetDateTimeFormats('D')[2].ToString();//Saturday 2005 11 05
dt.GetDateTimeFormats('D')[3].ToString();//Saturday 2005Year11Month5Day
dt.GetDateTimeFormats('M')[0].ToString();//11Month5Day
dt.GetDateTimeFormats('f')[0].ToString();//2005Year11Month5Day 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}",dt);//2005Year11Month5Day
string.Format("{0:f}", dt);//2005Year11Month5Day 14:23
string.Format("{0:F}",dt)}//2005Year11Month5Day 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);//11Month5Day
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);//2005Year11Month5Day 6:23:23
string.Format("{0:Y}",dt);//2005Year11Month
string.Format("{0}",dt);//2005-11-5 14:23:23
string.Format("{0:yyyyMMddHHmmssffff}",dt);
Calculate2Calculate the number of days between 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;
Calculate the number of days in a specific month and year
int days = DateTime.DaysInMonth(2007, 8);
days = 31;
Add or subtract one day from the date
DateTime dt = DateTime.Now;
dt.AddDays(1); //Increase one day
dt.AddDays(-1);//Decrease one day, other years are similar...
Date Conversion Functions in Oracle SQL
to_date("2007-6-6",'YYYY-MM-DD");
to_date("2007/6/6",'yyyy/mm/dd");