Error on date components

[Peter Bezolucci]

I found a problem with the date components for some reason the system will never accept that I enter a date of any first Sunday after the 15th of the month of October every year.

When I enter one of these dates and move the focus out of the component, the system automatically switches to the previous day.

You can notice the issue even in the pages of the demonstration site:
RadDatePicker
http://demos.telerik.com/aspnet-ajax/calendar/examples/datepicker/custompopup/defaultcs.aspx

RadDateInput
http://demos.telerik.com/aspnet-ajax/input/examples/raddateinput/firstlook/defaultcs.aspx

Calendar / Range Selection
http://demos.telerik.com/aspnet-ajax/calendar/examples/functionality/rangeselection/defaultcs.aspx

Dates with problems:
10/19/2014
10/20/2013
10/21/2012
10/16/2011
10/17/2010
10/18/2009
10/19/2008
10/21/2007
10/22/2006
10/16/2005
10/17/2004
10/19/2003
10/20/2002
10/21/2001
10/22/2000
10/17/1999
10/18/1998
10/19/1997
10/20/1996
10/22/1995
10/16/1994
10/17/1993
10/18/1992
10/20/1991
10/21/1990
10/22/1989
10/16/1988
10/18/1987
10/19/1986
10/20/1985
10/21/1984
10/16/1983
10/17/1982
10/18/1981
10/19/1980

[Vasil]

Hello Peter,

The problem comes because of the Daylight saving time change in this dates.
In some countries the clock is moving forward with one hour (or even 1.5 or 2 hours). So for example the "October 16 2011 00:00:00 AM" does not exist as valid time.

For example if you are in Brazil:
In 15 october you use GMT+2 time, and the first moment the time is:
11:59:59 PM on October 15 with no DST (UTC-3h)

And one moment later it gets:
October 16 1:00:00 AM  with DST +1h (UTC-2h)

And since the October 16 00:00:00 AM +1h does not exist(is not valid time), you can't select it in the DatePicker. The DatePicker itself selects the date with 00:00 hour.

You could manually change the selected time with one hour to 1 AM if you like. For example you could use this code:

<script type="text/javascript">
  function valueChanging(sender, args)
  {
    if (args.get_newValue() == "10/16/2011")
    {
      // 10/16/2011 for the given timezone will be auto-corrected to 10/15/2011 11:00 PM
      // Then in DateInput only 10/15/2011 will be shown, so change it to 10/16/2011 01:00 AM to be parsed as 10/16/2011

      //if you use DateTimePicker in the if statement check for "10/15/2011 11:00 PM"

      args.set_newValue("10/16/2011 01:00 AM");
    }
  }

</script>
<telerik:RadDatePicker runat="server" DateInput-ClientEvents-OnValueChanging="valueChanging">
</telerik:RadDatePicker>

Please not that the code-above currently will not work, and will work properly for the next release. There was a bug in the DatePicker/DateTimePicker that was causing even 10/16/2011 01:00 AM to be parsed as 10/15/2011, because the date and time is parsed separately by design. The fix will be included in the next release, and you would be able to select the date properly.

Best wishes,
Vasil
the Telerik team

[Peter Bezolucci]

Hello Vasin !

In case of using RadDateInput or RadDatePicker for a date of birth on one form registration, anyone born in one of these dates would have problems to properly inform the correct day unless the javascript code takes care of the whole possible range of dates.
(args.get_newValue() == "10/16/2011") ||
(args.get_newValue() == "10/17/2010") ||
(args.get_newValue() == "10/18/2009") ||
(args.get_newValue() == "10/19/2008") ||
(args.get_newValue() == "10/21/2007") ||
(args.get_newValue() == "10/22/2006") || ...

Is that right ?

Best wishes,
Peter

[Vasil]

Hi Peter Bezolucci,

If you use the picker for "date of birth" you probably don't need the time so you could modify it like:

args.set_newValue(args.get_newValue() + "02:00 AM");

Regards,
Vasil
the Telerik team

[Peter Bezolucci]

Hello Vasil !
Is there any chance to have a property like this?

UseDaylightSaving = "False"

Best Regards,
-Peter

[Vasil]

Hello Peter,

I also do really think that such a property would be useful, but we are limited from the JavaScript Date object itself. The Date object does not have a way to turn off the DaylightSaving correction. In the same time is out of the control scope to know which country when changes it time to make a reverse correction if such property is set.

Greetings,
Vasil
the Telerik team