Delegate AmbiguousTimeResolver

Chooses between two ZonedDateTime values that resolve to the same LocalDateTime.

Since 1.0.x

Availability net6.0, net8.0, netstandard2.0

Namespace: NodaTime.TimeZones

Assembly: NodaTime.dll

Syntax

public delegate ZonedDateTime AmbiguousTimeResolver(ZonedDateTime earlier, ZonedDateTime later)

Parameters

Type	Name	Description
ZonedDateTime	earlier	The earlier of the ambiguous matches for the original local date and time
ZonedDateTime	later	The later of the ambiguous matches for the original local date and time

Returns

Type	Description
ZonedDateTime	A ZonedDateTime in the target time zone; typically, one of the two input parameters.

Remarks

This delegate is used by CreateMappingResolver(AmbiguousTimeResolver, SkippedTimeResolver) when handling an ambiguous local time, due to clocks moving backward in a time zone transition (usually due to an autumnal daylight saving transition).

The returned value should be one of the two parameter values, based on the policy of the specific implementation. Alternatively, it can throw an AmbiguousTimeException to implement a policy of "reject ambiguous times."

See the Resolvers class for predefined implementations.

Implementations of this delegate can reasonably assume that the target local date and time really is ambiguous; the behaviour when the local date and time can be unambiguously mapped into the target time zone (or when it's skipped) is undefined.