TimeZone.GetUtcOffset Method (DateTime)
Returns the Coordinated Universal Time (UTC) offset for the specified local time.
Assembly: mscorlib (in mscorlib.dll)
This method returns the offset, or difference, between the time parameter and Coordinated Universal Time (UTC). That is:
time = UTC + offset
The method interprets the time zone of time based on its Kind property. If the value of the Kind property is DateTimeKind.Local or DateTimeKind.Unspecified, the method returns the offset of the local time zone. If the value of the Kind property is DateTimeKind.Utc, the method returns an offset equal to TimeSpan.Zero.
If the local time zone observes daylight saving time,applies the current adjustment rule to time when determining the offset of the local time zone. That is, the offset returned by reflects whether time falls in the time zone's standard time or its daylight saving time.
Themethod recognizes only the current daylight saving time adjustment rule for the local time zone. As a result, it is guaranteed to accurately return the UTC offset of a local time only during the period in which the latest adjustment rule is in effect. It may return inaccurate results if time is a historic date and time value that was subject to a previous adjustment rule.
Because the date and time value represented by time and this value's offset from UTC are not tightly coupled, a local or unspecified date and time value can return a different offset value when run on different computers or when run on the same computer under different time zones. If this behavior is undesirable, use a DateTimeOffset value instead. The DateTimeOffset data type tightly couples a date and time value with its offset from UTC.
Available since 1.1