How Can Recurring Events Be Scheduled Across Multiple Time Zones While Accurately Accounting for Daylight Saving Time?

Time Zone Considerations for Recurring Events Across Multiple Time Zones

Storing recurring events across multiple time zones requires careful consideration of Daylight Savings Time (DST). Here's how to handle this challenge:

Direct Approach

1. Store a 'dst' Flag: Indicate whether start/end dates were entered during DST.
2. Adjust Time by Hour: Modify the time by an hour if necessary to account for DST transitions.

Alternative Approach

1. Store Local Time and Time Zone: Record the event's local time and time zone, such as "08:00" and "America/New_York".
2. Calculate UTC Equivalents: Convert local dates/times to UTC, considering future time zone updates.
3. Store Future UTC Events: Project a list of future events in UTC for display purposes.

Caveat with Recurrence Pattern

With recurring events, if the start time occurs during a DST fall-back transition, determine whether the event occurs on the first, second, or both instances.

Complexity and Considerations

Scheduling future events across time zones is complex. Consider the following:

• Time Zone Updates: Subscribe to time zone database updates and recalculate UTC event times accordingly.
• UTC Scheduling with Local Time: While possible, it can be problematic if time zones change or events require adjustment to user's local time.
• Floating Times: Handle events that need to follow users across time zones appropriately.

The above is the detailed content of How Can Recurring Events Be Scheduled Across Multiple Time Zones While Accurately Accounting for Daylight Saving Time?. For more information, please follow other related articles on the PHP Chinese website!