ADO.NET连接数据库的两种方式
//实现了IDisposable接口的类,用using括起来 //插入数据 string connString = "Data Source=(local);Initial Catalog=Linq;Integrated Security=SSPI"; using (SqlConnection conn = new SqlConnection(connString)) { conn.Open(); using (SqlCommand cmd = conn.CreateCommand()) { cmd.CommandText = "insert into orders (Amt,Country,City) values(240,'中国','绍兴');"; cmd.ExecuteNonQuery(); Console.WriteLine("插入成功"); Console.ReadKey(); } } //用SqlDataReader方式读取数据 string connString = "Data Source=(local);Initial Catalog=Linq;Integrated Security=SSPI";//用windows用户登录 using (SqlConnection conn = new SqlConnection(connString)) { conn.Open(); using (SqlCommand cmd = conn.CreateCommand()) { cmd.CommandText = "select * from orders"; using (SqlDataReader reader = cmd.ExecuteReader()) { while (reader.Read()) { string city = reader.GetString(reader.GetOrdinal("city")); decimal amt = reader.GetDecimal(reader.GetOrdinal("amt")); Console.WriteLine(string.Format("城市:{0}, 金额:{1}", city, amt)); } } Console.ReadKey(); } } //用DataSet的方式来连接数据库 string connString = "Data Source=(local);Initial Catalog=Linq;Integrated Security=SSPI";//用windows用户登录 using (SqlConnection conn = new SqlConnection(connString)) { conn.Open(); using (SqlCommand cmd = conn.CreateCommand()) { cmd.CommandText = "select * from orders"; DataSet dataset = new DataSet(); SqlDataAdapter adapter = new SqlDataAdapter(cmd); /*把查询出来的结果填充到dataset中,并指定一个表面:orders *注意: * 如果不指定表名,直接用adapter.Fill(dataset)得方式填充,DataTable接收的时候根据索引号 * DataTable table = dataset.Tables[0]; */ adapter.Fill(dataset,"orders"); DataTable table = dataset.Tables["orders"]; for (int i = 0; i < table.Rows.Count; i++) { DataRow row = table.Rows[i]; string city = Convert.ToString(row["city"]); Console.WriteLine(city); } Console.ReadKey(); } }
posted on 2016-04-20 10:58 yangyong0615 阅读(239) 评论(0) 编辑 收藏 举报