PHP calculates the function of hours of the time between two timestamps

This is hour-by-hour PHP code

 
//Enter two timestamps to calculate the difference, which is the number of hours apart. If you return 2:10, the difference between the two input times is 2 hours and 10 minutes
function hours_min($start_time,$end_time){ 
if (strtotime($start_time) > strtotime($end_time)) list($start_time, $end_time) = array($end_time, $start_time); 
$sec = $start_time - $end_time; 
$sec = round($sec/60); 
$min = str_pad($sec%60, 2, 0, STR_PAD_LEFT); 
$hours_min = floor($sec/60); 
$min != 0 && $hours_min .= ':'.$min; 
return $hours_min; 
} 

The following is the day specific function code js

function get_date_different(){ 
var _date_1 = document.getElementById('date1').value.replace(/(^s*)|(s*$)/g,''); 
var _date_2 = document.getElementById('date2').value.replace(/(^s*)|(s*$)/g,''); 
_date_1 = new Date(_date_1); 
_date_2 = new Date(_date_2); 
var days= _date_2.getTime() - _date_1.getTime(); 
var time = parseInt(days / (1000 * 60 * 60 * 24)); 
document.getElementById('content').innerHTML = ' Difference between two dates  <strong style="color:red">'+time+'</strong>  Day! ';}</script>

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