Laravel Carbon how to change timezone without changing the hour

Question

I am trying to find a workaround for how I can convert the datetime stored in my Database as 'yyyy-mm-dd HH-mm-ss' and give it the timezone 'America/Los_Angeles'.

If I change the timezone, Carbon will automatically subtract 7 hours from the time, which is what happens when changing the time from UTC to PST, but the time in my DB is set for PST time. For example, I want the time to be 10am today, but it I change the timezone, Carbon will convert it to 3am today.

How can I make it where the timezone gets changed to PST but still keep the time at 10am? I need the timezone for an API call, which is why I need this figured out.

Answer 1

Use the shiftTimezone() method instead of setTimezone().

If you call setTimezone() on an existing instance of Carbon, it will change the date/time to the new timezone, for example:

$datetime = Carbon::createFromFormat('Y-m-d H:i:s', '2020-09-15 23:45:00'); echo $datetime->toAtomString() . "\n"; // 2020-09-15T23:45:00+00:00  $datetime->setTimezone('America/Los_Angeles'); echo $datetime . "\n"; // 2020-09-15T16:45:00-07:00 

However, calling shiftTimezone() instead will set the timezone without changing the time. Lets try it again from the start:

$datetime = Carbon::createFromFormat('Y-m-d H:i:s', '2020-09-15 23:45:00'); echo $datetime->toAtomString() . "\n"; // 2020-09-15T23:45:00+00:00  $datetime->shiftTimezone('America/Los_Angeles'); echo $datetime->toAtomString() . "\n"; // 2020-09-15T23:45:00-07:00 

Of course you can chain the methods together as well:

$datetime = Carbon::createFromFormat('Y-m-d H:i:s', '2020-09-15 23:45:00')     ->shiftTimezone('America/Los_Angeles'); echo $datetime->toAtomString() . "\n"; // 2020-09-15T23:45:00-07:00  

You can also "shift" the timezone by passing the timezone as part of the settings array:

$datetime = Carbon::createFromFormat('Y-m-d H:i:s', '2020-09-15 23:45:00')     ->settings(['timezone' => 'America/Los_Angeles']); echo $datetime->toAtomString() . "\n"; // 2020-09-15T23:45:00-07:00