Date + Time into timestamp [PHP]

Hi guys,

I want to convert date + time into timestamp.Problem is because my date and time are separate.

For example i have:

$time = $_POST['registration_date'];
$date = $_POST['registration_time'];

echo $date
Output:

2018-08-27

echo $time
Output:

00:09

So I need to get timestamp from it…

I’m find solution.This works for me.

$time = $_POST[‘registration_date’];
$time .= $_POST[‘registration_time’];