PHP add 45 Minutes to a Time with Loop [duplicate]

Question

I'm preparing an appointment script for entering visiting start hours and end hours like 09:00 and 20:00 and each visit period is 45 minutes.

I want to add 45 minutes from start time to end time within a loop. But with samples on internet I couldn't do it.

Visiting times are dynamic I mean it could be 09:00-20:00 or 11:00-23:00 etc.

The exact solution I'm trying to do is:

$visit_start = '09:00';
$visit_end   = '20:00';
$difference  =  $visit_end - $visit_start;
$i = 1;
while( $i <= $difference )
{
    print $visit_hour_list = $visit_start + 45;
    $i++;
}    

and the print out will be like:

09:00
09:45
10:30
11:15
12:00

until to end hour. But I have no clue how that could work.

Answer 1

As already answered in the similar question "How can I get a range of dates in php?", you can make use of the DatePeriod class in PHP to iterate over each 45 minute times' between a start and end time:

Demo:

<?php
/**
 * PHP add 45 Minutes to a Time with Loop
 *
 * @link https://stackoverflow.com/a/19399907/367456
 */

$begin = new DateTime("09:00");
$end   = new DateTime("20:00");

$interval = DateInterval::createFromDateString('45 min');

$times    = new DatePeriod($begin, $interval, $end);

foreach ($times as $time) {
    echo $time->format('H:i'), '-', 
         $time->add($interval)->format('H:i'), "\n"
         ;
}

Output:

09:00-09:45
09:45-10:30
10:30-11:15
11:15-12:00
12:00-12:45
12:45-13:30
13:30-14:15
14:15-15:00
15:00-15:45
15:45-16:30
16:30-17:15
17:15-18:00
18:00-18:45
18:45-19:30
19:30-20:15