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datetimedelphidelphi-xeweek-number

Retrieve Year from week number

Using Embarcadero Delphi, I need to populate a table with week number and the week year. The problem is at the end of December and starting January.

First case: Date "29/12/2024": is in the year 2024 and is referred to the 52° week of 2024. So I'll insert a record like: WEEK NUMBER = 52 WEEK YEAR = 2024

Second case: Date "30/12/2024": is in the year 2024 but is referred to the 1° week of 2025. So I need to insert a record like: WEEK NUMBER = 1 WEEK YEAR = 2025

How can I calculate this dynamically? Monday is the first date of the week

Solution

  • You can use this procedure:

    USES System.DateUtils;

PROCEDURE GetWeek(D : TDate ; OUT Week,Year : Cardinal);
  BEGIN
    Week:=WeekOf(D); Year:=YearOf(D);
    CASE MonthOf(D) OF
       1 : IF Week>50 THEN DEC(Year);
      12 : IF Week<50 THEN INC(Year)
    END
  END;

    It will return the Week and the corresponding Year for any given date in the Julian Calendar.