I am working on a Authorize.net form submit.
$api_login_id = $bookingSettingObj->getAuthorizeAPI();  // works
$transaction_key =  $bookingSettingObj->getAuthorizeTXN(); // works
$amount = /* What should i put here so i can echo the final price that is calculated by Javascript Function : addToAuthorizeForm(); ????? */ 
and the price calculation is done by javascript function addToAuthorizeForm. Please let me know what code should i add so the javascript funcrtion "addToAuthorizeForm" can echo succesfully..
UPDATE :
I am already using Ajax. Here is the javascript function i am using. I just need to know what code i put to execute this javascript function and echo final price..
    function addToAuthorizeForm() {
        $wbc('#slots_purchased').html('');
        var new_html = '';
        var i = 1;
        $wbc('#booking_slots').find('input').each(function() {
            if($wbc(this).attr('checked')) {
                var slot_id = $wbc(this).val();
                //ajax request to get data
                $wbc.ajax({
                  url: '<?php echo plugins_url('my_plugin/public');?>/ajax/getSlotInfo.php?slot_id='+$wbc(this).val(),
                  success: function(data) {
                      arrData=data.split("$");
                      if(arrData[1]>0) {
                          q = 1;
                          if($wbc('#seats_'+slot_id).val()!=undefined) {
                              q = $wbc('#seats_'+slot_id).val();
                          }
                          new_html += '<input type="hidden" name="item_name_'+i+'" value="'+arrData[0]+'" /><input type="hidden" name="amount_'+i+'" value="'+arrData[1]+'" /><input type="hidden" name="quantity_'+i+'" value="'+q+'" />';
                          $wbc('#slots_purchased').html(new_html);
                         i++;
                      }
                  }
                });
            }
        });
    }
 
    