


How to Generate a Timezone Drop-Down List with PHP using a Predefined List?
Oct 19, 2024 pm 09:57 PMGenerating a Drop Down List of Timezones with PHP
Question
When attempting to obtain a user's UTC offset during registration, which of the following methods is the most suitable for creating a timezone drop-down list?
- Using a predefined list of timezones with their corresponding UTC offsets
- Employing the PHP built-in DateTime class
Answer
The most reliable method is to utilize PHP's own timezone list using:
<code class="php">$tzlist = DateTimeZone::listIdentifiers(DateTimeZone::ALL);</code>
This method retrieves all of the available timezones from PHP and uses PHP's internal names for the timezones, avoiding the need for calculating DST offsets or relying on external lists that may become outdated.
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