System Namespace

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Represents an instance in time, typically expressed as a date and time of day.

DateTime Class Members

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Constructors Visibility Constructor Parameters public DateTime ( Int64 ticks ) public DateTime ( Int64 ticks , DateTimeKind kind ) public DateTime ( Int32 year , Int32 month , Int32 day ) public DateTime ( Int32 year , Int32 month , Int32 day , Calendar calendar ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , DateTimeKind kind ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Calendar calendar ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Int32 millisecond ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Int32 millisecond , DateTimeKind kind ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Int32 millisecond , Calendar calendar ) public DateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Int32 millisecond , Calendar calendar , DateTimeKind kind )   Fields Visibility Name Type public static MaxValue DateTime public static MinValue DateTime   Properties Visibility Name Value Type Accessibility public Date DateTime [ Get ] public Day Int32 [ Get ] public DayOfWeek DayOfWeek [ Get ] public DayOfYear Int32 [ Get ] public Hour Int32 [ Get ] public Kind DateTimeKind [ Get ] public Millisecond Int32 [ Get ] public Minute Int32 [ Get ] public Month Int32 [ Get ] public static Now DateTime [ Get ] public Second Int32 [ Get ] public Ticks Int64 [ Get ] public TimeOfDay TimeSpan [ Get ] public static Today DateTime [ Get ] public static UtcNow DateTime [ Get ] public Year Int32 [ Get ]   Methods Visibility Name Parameters Return Type public Add ( TimeSpan value ) DateTime public AddDays ( Double value ) DateTime public AddHours ( Double value ) DateTime public AddMilliseconds ( Double value ) DateTime public AddMinutes ( Double value ) DateTime public AddMonths ( Int32 months ) DateTime public AddSeconds ( Double value ) DateTime public AddTicks ( Int64 value ) DateTime public AddYears ( Int32 value ) DateTime public static Compare ( DateTime t1 , DateTime t2 ) Int32 public CompareTo ( DateTime value ) Int32 public CompareTo ( Object value ) Int32 public static DaysInMonth ( Int32 year , Int32 month ) Int32 public static Equals ( DateTime t1 , DateTime t2 ) Boolean public Equals ( DateTime value ) Boolean public Equals ( Object value ) Boolean public static FromBinary ( Int64 dateData ) DateTime public static FromFileTime ( Int64 fileTime ) DateTime public static FromFileTimeUtc ( Int64 fileTime ) DateTime public static FromOADate ( Double d ) DateTime public GetDateTimeFormats ( IFormatProvider provider ) String public GetDateTimeFormats ( ) String public GetDateTimeFormats ( Char format , IFormatProvider provider ) String public GetDateTimeFormats ( Char format ) String public GetHashCode ( ) Int32 public GetTypeCode ( ) TypeCode public IsDaylightSavingTime ( ) Boolean public static IsLeapYear ( Int32 year ) Boolean public static Parse ( String s , IFormatProvider provider , DateTimeStyles styles ) DateTime public static Parse ( String s , IFormatProvider provider ) DateTime public static Parse ( String s ) DateTime public static ParseExact ( String s , String format , IFormatProvider provider , DateTimeStyles style ) DateTime public static ParseExact ( String s , String format , IFormatProvider provider ) DateTime public static ParseExact ( String s , String formats , IFormatProvider provider , DateTimeStyles style ) DateTime public static SpecifyKind ( DateTime value , DateTimeKind kind ) DateTime public Subtract ( TimeSpan value ) DateTime public Subtract ( DateTime value ) TimeSpan public ToBinary ( ) Int64 public ToFileTime ( ) Int64 public ToFileTimeUtc ( ) Int64 public ToLocalTime ( ) DateTime public ToLongDateString ( ) String public ToLongTimeString ( ) String public ToOADate ( ) Double public ToShortDateString ( ) String public ToShortTimeString ( ) String public ToString ( IFormatProvider provider ) String public ToString ( String format , IFormatProvider provider ) String public ToString ( ) String public ToString ( String format ) String public ToUniversalTime ( ) DateTime public static TryParse ( String s , DateTime& result ) Boolean public static TryParse ( String s , IFormatProvider provider , DateTimeStyles styles , DateTime& result ) Boolean public static TryParseExact ( String s , String formats , IFormatProvider provider , DateTimeStyles style , DateTime& result ) Boolean public static TryParseExact ( String s , String format , IFormatProvider provider , DateTimeStyles style , DateTime& result ) Boolean

The DateTime value type represents dates and times with values ranging from 12:00:00 AM, 1/1/0001 CE ( Common Era ) to 11:59:59 PM, 12/31/9999 CE.

Time values are measured in 100-nanosecond units called "ticks", and a particular date is the number of ticks since 12:00 AM January 1, 1 CE in the GregorianCalendar calendar. For example, a ticks value of 31241376000000000L represents the date, Friday, January 01, 0100 12:00:00 AM. A DateTime value is always expressed in the context of an explicit or default calendar.

The DateTime and TimeSpan value types differ in that a DateTime represents an instance in time whereas a TimeSpan represents a time interval. This means, for example, that you can subtract one instance of DateTime from another to obtain the time interval between them. Or you could add a positive TimeSpan to the current DateTime to calculate a future date.

Time values can be added to, or subtracted from, an instance of DateTime. Time values can be negative or positive, and expressed in units such as ticks, seconds, or instances of TimeSpan. Methods and properties in this value type take into account details such as leap years and the number of days in a month.

Descriptions of time values in this type are often expressed using the coordinated universal time ( UTC ) standard, which was previously known as Greenwich Mean Time ( GMT ).

Calculations and comparisons of DateTime instances are only meaningful when the instances are created in the same time zone. For that reason, it is assumed that the developer has some external mechanism, such as an explicit variable or policy, to know in which time zone a DateTime instance was created. Methods and properties in this class always use the local time zone when making calculations or comparisons.

A calculation on an instance of DateTime, such as Add or Subtract, does not modify the value of the instance. Instead, the calculation returns a new instance of DateTime whose value is the result of the calculation.

This type inherits from IComparable, IFormattable, and IConvertible. Use the Convert class for conversions instead of this type's explicit interface member implementation of IConvertible.

TimeSpan   Calendar   GetUtcOffset

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