Reference for package '#rtl'

IsValidDateWeek

Check whether a given year/week/day of the week combination is a valid day.

Declaration

Source position: dateutil.inc line 89

  function IsValidDateWeek(const AYear: Word; const AWeekOfYear: Word; 
                          const ADayOfWeek: Word) : Boolean;

Description

IsValidDateWeek returns True if AYear, AWeekOfYear and ADayOfWeek form a valid date indication, or False otherwise.

AYear must be in the range 1..9999 to be valid.

The ADayOfWeek,ADayOfWeek values are checked to see whether the combination falls within the valid range of weeks for AYear.

See also

Name Description
IsValidDate Check whether a set of values is a valid date indication.
IsValidDateDay Check whether a given year/day of year combination is a valid date.
IsValidDateMonthWeek Check whether a given year/month/week/day of the week combination is a valid day
IsValidDateTime Check whether a set of values is a valid date and time indication.
IsValidTime Check whether a set of values is a valid time indication.

Example

Program Example10;
{ This program demonstrates the IsValidDateWeek function }
Uses SysUtils,DateUtils;
Var
  Y,W,D : Word;
  B : Boolean;
Begin
  For Y:=2000 to 2004 do
    begin
    B:=True;
    For W:=51 to 54 do
      For D:=1 to 7 do
        If B then
          begin
          B:=IsValidDateWeek(Y,W,D);
          If Not B then
            if (D=1) then
              Writeln(Y,' has exactly ',W,' weeks.')
            else
              Writeln(Y,' has ',W,' weeks and ',D-1,' days.');
          end;
    end;
End.