How to convert AM/PM to 24hrs format and convert to seconds in PHP

Here this blog is about, how to change date time format 12hr to 24 hrs and vice-versa.

I have given a simple examples which makes you better understand.

<?php

$booking_to_time = "4:45 PM";

$booking_date = "2020-12-01";

$time_in_24_hour_format = date("H:i:s", strtotime($booking_to_time));

$booking_date_time = $booking_date.' '.$time_in_24_hour_format;

$total_seconds = strtotime($booking_date_time);

Note:-

// 24-hour time to 12-hour time

$time_in_12_hour_format = date("g:i a", strtotime("16:45"));

// 12-hour time to 24-hour time

$time_in_24_hour_format = date("H:i", strtotime("4:45 PM"));