Google Apps脚本和Google日历的DST问题

Question

I am creating a school project for managing classes, I have a problem with time zones and DST here is my code:

javascript
dejt = new Date(thisYear, 8, day, beginTime, endTime, 0, 0);
dejt.toLocaleString("en-US", {timezone: "Europe/Belgrade"});

And I pass I through some functions until:

javascript
function makeCalendar(name, begin, end, calendar) {
    var eventSeries = CalendarApp.getCalendarById(calendar).createEventSeries(
        name,
        begin,
        end,
        CalendarApp.newRecurrence()
            .addWeeklyRule().interval(2).until(endDate)
    );
}

This works well until it hits October 29th after that everything is moved one hour earlier.

How do I manage DST?

EDIT:

After setting script to GMT (No daylight saving) things got more consistent and every date vas +00:00

Logs:
[19-02-12 11:30:15:809 CET] Sun Feb 17 00:00:00 GMT+00:00 2019
[19-02-12 11:30:15:810 CET] Mon Feb 18 00:00:00 GMT+00:00 2019
[19-02-12 11:30:24:051 CET] Mon Sep 03 14:00:00 GMT+00:00 2018
[19-02-12 11:30:24:503 CET] Mon Sep 03 14:50:00 GMT+00:00 2018

Now only problem is that recurring events just change time when daylight savings should be (Not a new bug, it was like this before).

EDIT:

New stuff I found out: If you edit events manually there is time zone box; My script makes it UTC but i can manually edit or remove it. Problem here is that I need to do it manually.

I also found .setTimeZone(string) in Google documentation: here , and here

The problem now is that i cannot make it work, no matter what i tried events would and up as UTC

Answer 1

Ok, after some digging into this, looks like there's something like a solution.

Google Calendar will look at script's timezone unless it is specified in the Date object you're passing into it. In your case it is not ( toLocaleString will not modify the original object, and if it would, you'd run into errors with passing strings into createEventSeries ). Anyway, your script's timezone seems to be Belgrade, and there's DST, time changes, etc.

Finally, possible solution. I don't know if Calendar service allows not to take DST in consideration so trying to get round the issue:

// function to convert date to UTC so that it retains original hours value
function convertDateToUTC(date, timezoneOffset) { 
    return new Date(date.getUTCFullYear(), date.getUTCMonth(), date.getUTCDate(), date.getUTCHours() + timezoneOffset, date.getUTCMinutes(), date.getUTCSeconds()); 
}
// 1 is the timezone offset from GMT
makeCalendar('test event', convertDateToUTC(beginDate, 1), convertDateToUTC(endDate, 1), calendar.getId());

Function convertDateToUTC is based on this answer .

Using this, I got (begin time was 7 am originally):