text: $(document).ready(function() {
  
      $('#couponTable').DataTable( {
          "paging": true,
          "ordering": true,
          "info": true,
          "pageLength": 5,
          "order": [[1, "asc"]],
          "processing": true,
          "serverSide": true,
          ajax: {
              "url": datatable_url,
              "type": "POST"
          },
          columns: [
              /*{
               className:      'details-control',
               orderable:      false,
               data:           null,
               defaultContent: ''
               },*/
              { data: "id"},
              { data: "created_date"},
              { data: "code"},
              { data: "order_id"},
              { data: "firstname"},
              { data: "email"},
              
              //{ data: "id"},
  
          ],
             "rowCallback": function( row, data,index ) {
              $('td:eq(0)', row).html(index+1);
              $('td:eq(4)', row).html(data.firstname+' '+data.lastname);
              //$('td:eq(4)', row).html('<a class="fa fa-trash" style="cursor:pointer;" onclick="deleteBanner('+data.id+')"></a> <a class="fa fa-edit" style="cursor: pointer;" href="'+edit_url+''+data.id+'"></a>');
          },
          order: [[0, 'asc']]
      });
  
  });
  