PHP - 找出两次之间的差异

Question

I'm trying to calculate the time difference (in hours) between two times inputted via a timepicker. I have working JavaScript code, but would rather use server side code to make this calculation as it's quite important. If you want me to post the working JS code let me know in comments.

Calculating the difference between the times is easy enough, but I require the output in a particular format. For example inputs of '07:30' and '14:00' would return 6.5 rather than 6.3. The reason for this is to make it easier for me to use this time difference in calculations.

PHP Code i've tried:

Attempt #1:

<?php
$start_time = new DateTime('07:30');
$end_time = new DateTime('14:00');
$time_diff = date_diff($start_time,$end_time);

echo $time_diff->format('%h.%i');
?>

Returns 6.3 as expected.

Attempt #2:

<?php
$start_time = "07:30";
$end_time = "14:00";
$start_time = str_replace(":", "", $start_time);
$end_time = str_replace(":", "", $end_time);
$res = $end_time - $start_time;
$result = $res / 100;
echo $result;
?>

Returns 6.7.

Tool used to test output: http://codepad.viper-7.com/

Answer 1

Just extract the minutes:

<?php
$start_time = new DateTime('07:30');
$end_time = new DateTime('14:00');
$time_diff = date_diff($start_time,$end_time);

$hours = (int)$time_diff->format('%h');
$hour_part =  ((int)$time_diff->format('%i')) / 60;
echo $hours + $hour_part;
?>

Make sure to change the type to (int) before any calculations.
If you divide the minutes by 60 you will get what part of a hour they represent.