จะ Select listbox คำนวนเวลา อัตโนมัติ คำนวนได้เเล้วแต่อยากเก็บค่าลงData Base

<script>
    $(document).ready(function() {    
  $('#txt2').bind('change keypress keyup blur', function() {
      var Time1= $("#txt1").val();
      var Time2= $("#txt2").val();
      start = Time1.split(":");
      end = Time2.split(":")
      var startTime = new Date(0, 0, 0, start[0], start[1], 0);
      var endTime = new Date(0, 0, 0, end[0], end[1], 0);
      var diff_time = endDate.getTime() - startDate.getTime();
      var hours = diff_time /(1000 * 60 * 60);
      console.log(hours );//ได้ค่าเป็น ชม. ไปต่อเอาเอง
    });
   });
</script>

<script>
    $(document).ready(function(){
      $('#txt1,#txt2').on('change',function(){
        var time_in = $('#txt1 option:selected').text();
        var time_out = $('#txt2 option:selected').text();
        
        var st = new Date("01/01/2000 "+time_in);
        var en = new Date("01/01/2000 "+time_out);
  
  //if(parseInt(en.getTime()) < parseInt(st.getTime())){
//alert('เวลาออกน้อยกว่าเข้าครับ');
//return false;
 // }
 
 
        var result = parseInt(((en.getTime() - st.getTime()))/1000); // in second
        var sec = result % 60; result = Math.floor( result / 60);
        var m = result % 60; result = Math.floor( result / 60);
        var h = result % 24;
        var value = ('0'+h).slice(-2)+':'+('0'+m).slice(-2)+':'+('0'+sec).slice(-2);
        $('#time_diff').val(value);
      })
    });
   </script>

	<script>
  
$(document).ready(function(){
$('#txt1,#txt2').on('change',function(){
var time_in = $('#txt1 option:selected').text();
var time_out = $('#txt2 option:selected').text();

var st = new Date("01/01/2000 "+time_in);
var en = new Date("01/01/2000 "+time_out);

//if(parseInt(en.getTime()) < parseInt(st.getTime())){
//alert('เวลาออกน้อยกว่าเข้าครับ');
//return false;
// }

var result = parseInt(((en.getTime() - st.getTime()))/1000); // in second			
var sec = result % 60; result = Math.floor( result / 60);
var m = result % 60; result = Math.floor( result / 60);
var h = result % 24;
if (h>=5 )
h-=1;
var value = ('0'+h).slice(-2)+':'+('0'+m).slice(-2)+':'+('0'+sec).slice(-2);

$('#time_diff').val(value);
})
});
</script>