- var_dump: documentation ( source)
- mktime: documentation ( source)
- date: documentation ( source)
<?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));