while (dataReader.Read())
                {
                    string name = (string)dataReader["name"];
                    string type=(string)dataReader["type"];
                    int number = (int)dataReader["number"];
                    //float price=(float)dataReader["price"];

                    ListViewItem item = item = new ListViewItem(); ;
                    item.Tag=(int)dataReader["id"];
                    item.Text = name;
                    item.SubItems.Add(type);
                    item.SubItems.Add(number.ToString());
                    //item.SubItems.Add(price.ToString());
                    lvShangPin.Items.Add(item);
                }
                dataReader.Close();
加//的两行造成程序报错