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<?php $starttime = ['year' => 2019, 'month' => 5, 'day' => 10, 'hour' => 20, 'minute' => 15]; $timestamp = mktime( $starttime['hour'], $starttime['minute'], 0, $starttime['month'], $starttime['day'], $starttime['year'] ); var_dump($timestamp); var_dump(date('Y-m-d H:i:s', $timestamp));
Output for 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33, 8.0.0 - 8.0.12, 8.0.14 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
int(1557512100) string(19) "2019-05-10 20:15:00"
Output for 7.3.32 - 7.3.33, 8.0.13
int(1557519300) string(19) "2019-05-10 20:15:00"

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