## Summary I want to suggest some extensions to dateutils functions: 1. Overload `IncDay`, `IncHour`, `IncMinute`, `IncSecond` functions so that the "ANumberOfXxx" part is of type `Double`. Reason: These are very useful helper functions, but code is better readable if you could write `IncDay (ADateTime, 1.5)` instead of `IncHour (ADateTime, 1.5*24.0)`. Same for IncHour, etc. 2. `TryISO8601ToDate` internally calls `TryISOTZStrToTZOffset`, but the latter is of no use to get the time offset of a complete ISO date string of the form `2024-01-01T12:34:56+01:00` because it expects the offset part _alone_. I haven't found any other access to obtain the time offset either, so I suggest adding an overload like this: `function TryISO8601ToDate(const DateString: string; out ADateTime: TDateTime; out ATimeOffset: Double; ReturnUTC: Boolean = True):Boolean;`, returning the time offset in hours. ## System Information - **Operating system:** Windows - **Processor architecture:** x86-64 - **Device:** Computer ## Example Project I suggest these modifications to `dateutil.inc`: ```text 311a312 > Function IncDay(const AValue: TDateTime; const ANumberOfDays: Double): TDateTime; 313a315 > Function IncHour(const AValue: TDateTime; const ANumberOfHours: Double): TDateTime; 315a318 > Function IncMinute(const AValue: TDateTime; const ANumberOfMinutes: Double): TDateTime; 316a320 > Function IncSecond(const AValue: TDateTime; const ANumberOfSeconds: Double): TDateTime; 319a324 > Function IncMilliSecond(const AValue: TDateTime; const ANumberOfMilliSeconds: Double): TDateTime; 483a489 > Function TryISO8601ToDate(const DateString: string; out ADateTime: TDateTime; out ATimeOffset: Double; ReturnUTC : Boolean = True) : Boolean; 1740a1747,1753 > Function IncDay(const AValue: TDateTime; const ANumberOfDays: Double): TDateTime; > begin > Result:=AValue+ANumberOfDays; > MaybeSkipTimeWarp(AValue,Result); > end; > > 1756a1770,1779 > Function IncHour(const AValue: TDateTime; const ANumberOfHours: Double): TDateTime; > begin > if AValue>=0 then > Result:=AValue+ANumberOfHours/HoursPerDay > else > Result:=IncNegativeTime(Avalue,ANumberOfHours/HoursPerDay); > MaybeSkipTimeWarp(AValue,Result); > end; > > 1772a1796,1805 > Function IncMinute(const AValue: TDateTime; const ANumberOfMinutes: Double): TDateTime; > begin > if AValue>=0 then > Result:=AValue+ANumberOfMinutes/MinsPerDay > else > Result:=IncNegativeTime(Avalue,ANumberOfMinutes/MinsPerDay); > MaybeSkipTimeWarp(AValue,Result); > end; > > 1788a1822,1831 > Function IncSecond(const AValue: TDateTime; const ANumberOfSeconds: Double): TDateTime; > begin > if AValue>=0 then > Result:=AValue+ANumberOfSeconds/SecsPerDay > else > Result:=IncNegativeTime(Avalue,ANumberOfSeconds/SecsPerDay); > MaybeSkipTimeWarp(AValue,Result); > end; > > 1804a1848,1857 > Function IncMilliSecond(const AValue: TDateTime; const ANumberOfMilliSeconds: Double): TDateTime; > begin > if Avalue>=0 then > Result:=AValue+ANumberOfMilliSeconds/MSecsPerDay > else > Result:=IncNegativeTime(Avalue,ANumberOfMilliSeconds/MSecsPerDay); > MaybeSkipTimeWarp(AValue,Result); > end; > > 3119c3172,3181 < Function TryISO8601ToDate(const DateString: string; out ADateTime: TDateTime;ReturnUTC : Boolean = True) : Boolean; --- > Function TryISO8601ToDate(const DateString: string; out ADateTime: TDateTime; ReturnUTC : Boolean = True) : Boolean; > > Var > time_offset: Double; // will be discarded here > > begin > Result := TryISO8601ToDate(DateString, ADateTime, time_offset, ReturnUTC); > end; > > Function TryISO8601ToDate(const DateString: string; out ADateTime: TDateTime; out ATimeOffset: Double; ReturnUTC : Boolean = True) : Boolean; 3158a3221 > aTimeOffset:=TZOffSet/MinsPerHour; ```