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IsValidDateWeek function

In unit DateUtils

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

Declaration

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

Arguments

AYear

Year.

AWeekOfYear

Week in the year.

ADayOfWeek

Day in the week.

Function result

True if the given combination is a valid date, False otherwise.

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

Example: ex10

pascal
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.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.