ปัญหาเพิ่มแถวจากการกดปุ่มเพิ่มแถวแล้ว ไม่สามารถส่งค่าเข้าไปยังแถวที่เพิ่มได้

 <!------------------------------------- เพิ่ม textbox -------------------------------------------------------------------------------------->
<script>  
 $(document).ready(function(){  
      var i=1;  
      $('#add').click(function(){  
           i++;  
           $('#dynamic_field').append('<tr id="row'+i+'">
                                         <td align="center">
                                            <div class="input-group"><input type="text"  class="form-control" placeholder="Search" id="wit_item_code[]"  name="wit_item_code[]" value="" disabled >
                                            <div class="input-group-btn"><button class="btn btn-info" type="button"  data-toggle="modal" data-target="#searchitem"><i class="glyphicon glyphicon-search"></i></button></div></div></form></td>															
                                        <td align="center"><input type="text" name="w_itemname[]" id="w_itemname[]"  style="width:300px;" class="form-control name_list"></td>															
                                        <td align="center"><input type="text" name="w_itemqty[]" id="w_itemqty[]"  class="form-control name_list"></td>		<td align="center"><input type="text" name="w_unitcode[]" id="w_unitcode[]"  class="form-control name_list"></td>															
                                        <td align="center"><input type="text" name="w_price[]" id="w_price[]"  class="form-control name_list"></td>	        <td align="center"><input type="text" name="w_com[]" id="w_com[]"  class="form-control name_list"></td>                              
                                        <td><button type="button" name="remove" id="'+i+'" class="btn btn-danger btn_remove">X</button></td></tr>');  
      });  
      $(document).on('click', '.btn_remove', function(){  
           var button_id = $(this).attr("id");   
           $('#row'+button_id+'').remove();  
      });  
      $('#submit').click(function(){            
           $.ajax({  
                url:"withdraw_check.php",  
                method:"POST",  
                data:$('#add_name').serialize(),  
                success:function(data)  
                {  
                     alert(data);  
                     $('#add_name')[0].reset();  
                }  
           });  
      });  
 });  
 </script> 
  <!------------------------------------- ส่งค่าเข้า TEXTBOX -------------------------------------------------------------------------------------->
	<script>
    function add_id(obj){
    var val = obj.value;
    console.log(val);
    document.getElementById('wit_item_code[]').value = val;
}
</script>