IncWeek returns the given date, incremented by the number of weeks given as the ANumberOfWeeks parameter.

ANumberOfWeeks can be negative, to return a date, earlier by the specified number of weeks.

The time of day specified by AValue, is copied to the result.

Declaration: Function IncWeek(const AValue: TDateTime; const ANumberOfWeeks: Integer): TDateTime;

This is a simple example.

procedure OnMapEvent(var Value:Variant);
var
TheDate, ThatDate, BackDate : TDateTime;
begin
//Returns a date incremented by 10 weeks
TheDate := Now;
ThatDate := IncWeek(TheDate, 10);
BackDate := IncWeek(TheDate,-10);
LogInfo(FormatDateTime('yyyy-mm-dd hh:nn:ss.zzz', TheDate));
LogInfo(FormatDateTime('yyyy-mm-dd hh:nn:ss.zzz', ThatDate));
LogInfo(FormatDateTime('yyyy-mm-dd hh:nn:ss.zzz', BackDate));
end;