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Request a Feature Report a Bug
Unplanned
Last Updated: 15 Oct 2026 13:47 by ADMIN
Jihong
Created on: 10 Oct 2024 06:19
Category: Calendar
Type: Bug Report
2
RadCalendar: WeekNumber is not correct when CalendarWeekRule.FirstFourDayWeek

To reproduce: 

CultureInfo culture = new CultureInfo("en-US");
culture.DateTimeFormat.FirstDayOfWeek = DayOfWeek.Monday;
culture.DateTimeFormat.CalendarWeekRule = CalendarWeekRule.FirstFourDayWeek;
this.radCalendar1.ShowRowHeaders = true;
this.radCalendar1.Culture = culture;

 

3 comments
ADMIN
Nadya | Tech Support Engineer
Posted on: 15 Oct 2026 13:47

Hi, Bert,

I updated the priority of this item. We will do our best to include a fix in some of our next releases. Make sure that you follow the item so that you can receive status updates on your email.

Regards,
Nadya | Tech Support Engineer
Progress Telerik

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Bert
Posted on: 13 Oct 2026 10:22

We are experiencing the same problem.

I have tried the suggested solution to set CalenderWeekRule to CalendarWeekRule.FirstDay but this does not solve the problem completely. This is correct:

But when I navigate to the previous month I get this:

Weeknumber 53 is not correct, this should be 1.

I hope this issue can be fixed in an upcoming release.

ADMIN
Nadya | Tech Support Engineer
Posted on: 10 Oct 2024 06:27

Hello, Jihong,

You can set CalendarWeekRule.FirstDay:

culture.DateTimeFormat.CalendarWeekRule = CalendarWeekRule.FirstDay;

RadCalendar:

MS MonthCalendar:

Regards,
Nadya | Tech Support Engineer
Progress Telerik

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