p; Console.WriteLine(); Console.WriteLine("Categories After Insert"); Console.WriteLine("------------------------------"); scd.ReadData(); // use ExecuteNonQuery method for Update scd.UpdateData(); Console.WriteLine(); Console.WriteLine("Categories After Update"); Console.WriteLine("------------------------------"); scd.ReadData(); // use ExecuteNonQuery method for Delete scd.DeleteData(); Console.WriteLine(); Console.WriteLine("Categories After Delete"); Console.WriteLine("------------------------------"); scd.ReadData(); // use ExecuteScalar method int numberOfRecords = scd.GetNumberOfRecords(); Console.WriteLine(); Console.WriteLine("Number of Records: {0}", numberOfRecords); } /// <summary> /// use ExecuteReader method /// </summary> public void ReadData() { SqlDataReader rdr = null; try { // Open the connection conn.Open(); // 1. Instantiate a new command with a query and connection SqlCommand cmd = new SqlCommand("select CategoryName from Categories", conn); // 2. Call Execute reader to get query results rdr = cmd.ExecuteReader(); // print the CategoryName of each record while (rdr.Read()) { Console.WriteLine(rdr[0]); } } finally { // close the reader if (rdr != null) { rdr.Close(); } // Close the connection if (conn != null) { conn.Close(); } } } /// <summary> /// use ExecuteNonQuery method for Insert /// </summary> public void InsertData() { try { // Open the connection conn.Open(); &nb << 上一页 [11] [12] [13] [14] [15] 下一页 |