public override void ShowData(DataGridView dataGridView)
        {
            if (id == 0)
            {
                _query = "SELECT id,name,fathername,cnic,mobile FROM Student WHERE class='" + _class + "' AND section='" + _section + "' AND status='" + _status + "'";
            }
            else if (id != 0)
            {
                _query = "SELECT id,name,fathername,cnic,mobile FROM Student WHERE id='" + id + "'";
            }

            DbClient.DatGridFill(dataGridView, _query);
        }
        public override void ShowData(DataGridView dataGridView)
        {
            if (id == 0)
            {
                _query = "SELECT id,name,cnic,fathername,mobile FROM Staff WHERE designation='" + _designation + "' AND status='" + _status + "' AND qualification='" + qualification + "'";
            }

            else if (id != 0)
            {
                _query = "SELECT id,name,cnic,fathername,mobile FROM Staff WHERE id='" + id + "'";
            }

            DbClient.DatGridFill(dataGridView, _query);
        }