New (2001, 2, 3.5) #= # An optional argument, the offset, indicates the difference between the local time and UTC. For example, Rational(3,24) represents ahead of 3 hours of UTC, Rational(-5,24) represents behind of 5 hours of UTC. The offset should be -1 to +1, and its precision is assumed at. Using the DateTime object lets your create a datetime, just like the procedural functions, except that you keep a reference to an instance. A DateTimeFormatInfo object that defines the format of date and time data. A custom object that implements the IFormatProvider interface. Its GetFormat method returns a DateTimeFormatInfo object that provides formatting information. If provider is null, the DateTimeFormatInfo associated with the current culture is used.Manages conversion of date and time information between 4 different formats: Strings, Dates, epoch times, and julian days, with the Strings using primarily the GMT timezone.
There are 6 static final DateFormat objects that can be used by applications directly to format and parse Dates. The Strings that are returned by these DateFormat objects are complete in the sense that they can be parsed back to the Date that was used to generate them, with at least 1 second precision.
ASSUMPTION: if timezone information is not part of the DateFormat format String, then the GMT time zone is assumed.
Method getDate(String) will take a String that was generated by any of the DateFormat objects and return the correct Date.
getDate(String) will try to parse the String as an int (interpreted as a jdate) and then as a double (interpreted as epoch time). It attempts to parse the String using the DataFormat objects only after attempts to parse the String as an int or a double fail.
Methods toGMT() and toLocal() convert milliseconds since 1970 between GMT timezone and local time zone.
Date objects store milliseconds since 1970 GMT. Unfortunately, when JDBC returns an oracle.sql.TIMESTAMP object from the database, the year, month, day, hour, minute, second and nanosecond information is converted to milliseconds since 1970 local time (not GMT). This means that in order to construct a java.util.Date object one should use:
Converts the value of the current DateTime object to local time.
An object whose Kind property is Local, and whose value is the local time equivalent to the value of the current DateTime object, or MaxValue if the converted value is too large to be represented by a DateTime object, or MinValue if the converted value is too small to be represented as a DateTime object.
The following example demonstrates the ToLocalTime method. Note that the exact output depends on the current culture and the local time zone of the system on which it is run.
The following example uses the SpecifyKind method to demonstrate how the Kind property influences the ToLocalTime and ToUniversalTime conversion methods.
The local time is equal to the Coordinated Universal Time (UTC) time plus the UTC offset. For more information about the UTC offset, see TimeZoneInfo.GetUtcOffset. The conversion also takes into account the daylight saving time rule that applies to the time represented by the current DateTime object.
Python Datetime Gmt Time
On Windows XP systems, the ToLocalTime method recognizes only the current adjustment rule when converting from UTC to local time. As a result, conversions for periods before the current adjustment rule came into effect may not accurately reflect the difference between UTC and local time.
Starting with the .NET Framework version 2.0, the value returned by the ToLocalTime method is determined by the Kind property of the current DateTime object. The following table describes the possible results.
|Utc||This instance of DateTime is converted to local time.|
|Local||No conversion is performed.|
|Unspecified||This instance of DateTime is assumed to be a UTC time, and the conversion is performed as if Kind were Utc.|
The ToLocalTime method converts a DateTime value from UTC to local time. To convert the time in any designated time zone to local time, use the TimeZoneInfo.ConvertTime method.
The value returned by the conversion is a DateTime whose Kind property always returns Local. Consequently, a valid result is returned even if ToLocalTime is applied repeatedly to the same DateTime.
Notes to Callers
You can use the ToLocalTime() method to restore a local date and time value that was converted to UTC by the ToUniversalTime() or FromFileTimeUtc(Int64) method. However, if the original time represents an invalid time in the local time zone, it will not match the restored value. When the ToLocalTime() method converts a time from UTC to the local time zone, it also adjusts the time so that is valid in the local time zone.
For example, the transition from standard time to daylight saving time occurs in the U.S. Pacific Time zone on March 14, 2010, at 2:00 A.M., when the time advances by one hour, to 3:00 A.M. This hour interval is an invalid time, that is, a time interval that does not exist in this time zone. The following example shows that when a time that falls within this range is converted to UTC by the ToUniversalTime() method and is then restored by the ToLocalTime() method, the original value is adjusted to become a valid time. You can determine whether a particular date and time value may be subject to modification by passing it to the IsInvalidTime(DateTime) method, as the example illustrates.