从 ms 访问中获取表数

我正在使用C#为cachier开发一个程序。对数据库使用 ms 访问的程序。不知何故，数据库没有输入到表中。我的问题在哪里？这是代码：

private void buttonCloseCart_Click（Object sender， EventArgs e） { 连接。连接字符串 = 连接字符串; 连接。打开（）; OleDbCommand cmd1 = new OleDbCommand（"INSERT INTO ReceiptItem （ItemID， Quantity， UnitPrice） VALUES （@itemID， @temp_item_quantity， @temp_item_price）"， connect）; CMD1.Parameters.Add（"@temp_item"， OleDbType.Char， 20）; CMD1.Parameters.Add（"@temp_item_quantity"， OleDbType.Integer， 20）; CMD1.Parameters.Add（"@temp_item_price"， OleDbType.Double， 20）; CMD1.Parameters.Add（"@cart_sum"， OleDbType.Double， 20）; CMD1.Parameters.Add（"@itemID"， OleDbType.Integer， 20）;

        for (int i = 0; i < baught_items.Count; i++)
        {
            /*Set temporary reference to the objects located on the List*/ 
            string temp_item = baught_items[i].ToString();
            int temp_item_quantity = baught_items_quantity[i];
            double temp_item_price = baught_items_price[i];
            double temp_total_item_price = total_items_price[i];
            /*Set the connection to the CachierPro DataBase*/
            OleDbConnection myconnection = new OleDbConnection(connect.ConnectionString);
            myconnection.Open();
            //OleDbConnection myconnection1 = new OleDbConnection(connect.ConnectionString);
            //myconnection1.Open();
            /*********************************************/
            /*This Action get the Item Name directly from the database according to the item name in the cart*/
            //OleDbConnection dataConnection = new OleDbConnection();
            //dataConnection.ConnectionString = connString;
            //dataConnection.Open();
            //OleDbConnection oledbConn = new OleDbConnection(connString);
            //oledbConn.Open();
            //OleDbCommand myCommand1 = new OleDbCommand();
            //myCommand1.Connection = myconnection1;
            //myCommand1.Connection.Close();
            OleDbCommand cmd = new OleDbCommand("SELECT [ItemID] FROM ItemsList WHERE [ItemName] = " + "'"+temp_item +"'" , connect);
            OleDbDataReader dataReader = cmd.ExecuteReader();
            if (dataReader.Read()) { }
            int itemID = dataReader.GetInt32(0);
            /********************************************/
            /*Initialize the Command ment for the Query*/
            OleDbCommand myCommand = new OleDbCommand();
            myCommand.Connection = myconnection;
            //myCommand.ExecuteNonQuery();
            myCommand.Connection.Close();
            //dataConnection.Close();
            //oledbConn.Close();
            myconnection.Close();
            dataReader.Close();
            /*Enter the first query*/

            if (connect.State == ConnectionState.Open)
            {
                try
                { int addedCount = cmd.ExecuteNonQuery(); }
                catch (Exception expe)
                { MessageBox.Show(expe.Message); connect.Close(); }
            }
            else
            {
                MessageBox.Show("Connection Failed");
            }
        }
        OleDbDataAdapter da = new OleDbDataAdapter();
        da.SelectCommand = new OleDbCommand("SELECT * FROM ReceiptItem", connect);
        DataTable dt = new DataTable();
        da.Fill(dt);
        textBoxCurrentCartSumTXT.Clear();
        textBoxPricePerOneTXT.Clear();
        textBoxQuantityTXT.Clear();
        textBoxSumForCurrentItemTXT.Clear();
        connect.Close();

        }