class AdoDemo    {        static string strConn = @"Data Source=server1;Initial Catalog=NameCard;Integrated Security=False;User ID=sa;Password=******;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False";        static void Main(string[] args)        {            //InsertData();//1.1插入新数据练习            //InsertDataParameters();//1.2插入新数据练习,Parameters方法            //updataData();//更新数据            //DelData();//删除数据            //QueryDataByDs();//使用dataadapter,dataset查询数据            //QueryByDr();//使用dataread查询数据            //querybyDt();//使用datatable查询数据            Console.ReadKey();        }        #region 1.1插入新数据        private static void InsertData()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                using (SqlCommand sqlcmd = connection.CreateCommand())                {                    string strCmd = "insert into Customer (region,Name,Department) values (‘jinan‘,‘li‘,‘shandong‘)";                    sqlcmd.CommandText = strCmd;                    if (sqlcmd.ExecuteNonQuery() > 0)                    {                        Console.WriteLine("插入成功");                    }                    else                    {                        Console.WriteLine("插入失败");                    }                }            }        }        #endregion        #region 1.2插入新数据,Parameters方法        private static void InsertDataParameters()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                using (SqlCommand sqlCmd = connection.CreateCommand())                {                    string sqlStr = "insert into Customer (region,Name,Department) values (@region,@name,@depart)";                    sqlCmd.CommandText = sqlStr;                    sqlCmd.Parameters.Add("@region", SqlDbType.NVarChar);                    sqlCmd.Parameters["@region"].Value = http://www.mamicode.com/"Sichuan";                    sqlCmd.Parameters.AddWithValue("@name", "Chong");                    sqlCmd.Parameters.AddWithValue("@depart", "qing");                    if (sqlCmd.ExecuteNonQuery() > 0)                    {                        Console.WriteLine("插入成功");                    }                    else                    {                        Console.WriteLine("插入失败");                    }                }            }        }        #endregion        #region 2 修改数据练习        private static void updataData()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                using (SqlCommand sqlCmd = connection.CreateCommand())                {                    string cmdStr = "update Customer set Name=‘@name‘ where id=‘2845‘";                    sqlCmd.CommandText = cmdStr;                    if (sqlCmd.ExecuteNonQuery() > 0)                    {                        Console.WriteLine("插入成功");                    }                    else                    {                        Console.WriteLine("插入失败");                    }                }            }        }        #endregion        #region 3 删除数据 练习        private static void DelData()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                using (SqlCommand sqlcmd = connection.CreateCommand())                {                    string cmdStr = "delete from Customer where id >=‘2840‘";                    sqlcmd.CommandText = cmdStr;                    if (sqlcmd.ExecuteNonQuery() > 0)                    {                        Console.WriteLine("删除成功");                    }                    else                    {                        Console.WriteLine("删除失败");                    }                }            }        }        #endregion        #region 4.1 使用dataadapter,dataset查询数据        private static void QueryDataByDs()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                string cmdStr = "select top 20 * from Customer";                SqlDataAdapter sqlda = new SqlDataAdapter(cmdStr, strConn);                DataSet ds = new DataSet();                sqlda.Fill(ds, "customer");                foreach (DataRow dr in ds.Tables[0].Rows)                {                    Console.WriteLine("ID={0},region={1},department={2},name={3},phone1={4}", dr[0], dr[1], dr[2], dr[3], dr[4]);                }            }        }        #endregion        #region 4.2 使用datareader查询数据        private static void QueryByDr()        {            using (SqlConnection connection = new SqlConnection(strConn))            {                connection.Open();                using (SqlCommand sqlCmd = connection.CreateCommand())                {                    string cmdStr = "select top 10 * from Customer";                    sqlCmd.CommandText = cmdStr;                    SqlDataReader sqlDr = sqlCmd.ExecuteReader();                    while (sqlDr.HasRows)//是否返回数据                    {                        while (sqlDr.Read())//从第一行开始顺序读取数据集到最后一行                        {                            Console.WriteLine("ID={0},region={1},department={2},name={3},phone1={4}", sqlDr[0].ToString(), sqlDr[1].ToString(), sqlDr[2].ToString(), sqlDr[3].ToString(), sqlDr[4].ToString());                        }                    }                }            }        }        #endregion        #region 4.3 使用datatable查询数据        private static void querybyDt()        {            SqlConnection connection = new SqlConnection(strConn);            connection.Open();            string cmdStr = "select top 10 * from Customer";            SqlDataAdapter sqlda = new SqlDataAdapter(cmdStr,connection);            DataTable dt = new DataTable();            sqlda.Fill(dt);            foreach (DataRow item in dt.Rows)            {                Console.WriteLine("{0},{1},{2}", item[0].ToString(), item[1].ToString(), item[2].ToString());            }            connection.Close();        }        #endregion    }