php - adjusting for timezones

问题

Alright so I have this code which makes a list of dates:

$dates = array();
                for($i = 1; $i < 10; $i++)
                {
                    $datetime = mktime(12, 0, 0, date('n'), date('j') + $i, date('Y'));
                    if(date('N', $datetime) != 6 && date('N', $datetime) != 7)
                    {
                        $dates[date('l, F jS', $datetime)] = date('l, F jS', $datetime);
                    }
                }

The dates are tomorrow and on as long as they are not Saturday or Sunday.

Now the problem is "tomorrow" is being changed at like 8:00 PM EST.

To explain, say it's Wednesday. The first option in the list should be Thursday. However, once it is 8:00 PM EST, then the first option is Friday. Instead of changing at 8:00 PM EST I'd like it to change at 3:00 AM EST (so on Thursday @ 2:00 AM it should still offer Thursday as a choice)

回答1:

I think you are getting your time zones confused currently. 8PM EDT = Midnight UTC.

Anyway, in PHP 5.3:

$one_day = new DateInterval('P1D');
$tz = new DateTimeZone('America/New_York');
$start = new DateTime('now', $tz);

if ($start->format('G') >= 3)
  $start->add($one_day);

foreach (new DatePeriod($start, $one_day, 10) as $date)
{
  if ($date->format('N') < 6)
    echo $date->format('l, F jS')."\n";
}

The logic remains the same if you are on < 5.3, just have to do things with the other functions like strtotime(), date(), etc:

$one_day = 86400;
date_default_timezone_set('America/New_York');
$start = time();

if (date('G', $start) >= 3)
  $start += $one_day;

for ($i = 0, $date = $start; $i < 10; ++$i, $date += $one_day)
{
  if (date('N', $date) < 6)
    echo date('l, F jS', $date)."\n";
}

I think that should work.

来源：https://stackoverflow.com/questions/3878790/php-adjusting-for-timezones

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php

datetime

date

time

timezone