private void button2_Click(object sender, RoutedEventArgs e)

         {

             using (SqlConnection conn = new SqlConnection("Data Source=XX;Initial Catalog=DBData;User ID=sa;Password=111111"))

             {

                 conn.Open();

                 using (SqlCommand cmd = conn.CreateCommand())

                 {

                     cmd.CommandText = "insert [DBData].[dbo].[T_Student] (Number,Name,Score) output inserted.ID values('012345','LiLei','89')";

                     long id = (long)cmd.ExecuteScalar(); //ExecuteScalar()：执行查询，返回结果集中的第一行的第                                                                                                              一列

                     MessageBox.Show("操作成功: i=" + id.ToString());

                 }

             }

         }

 private void button2_Click(object sender, RoutedEventArgs e)

         {

             using (SqlConnection conn = new SqlConnection("Data Source=XX;Initial Catalog=DBData;User ID=sa;Password=111111"))

             {

                 conn.Open();

                 using (SqlCommand cmd = conn.CreateCommand())

                 {

                     cmd.CommandText = "Select * from [DBData].[dbo].[T_Student] where score<160";

                     using (SqlDataReader reader = cmd.ExecuteReader())

                     {

                         while (reader.Read())

                         {

                             MessageBox.Show(reader.GetString());  //获取指定列的字符串的值

                         }

                     }

                 }

             }

         }

 private void button2_Click(object sender, RoutedEventArgs e)

         {

             using (SqlConnection conn = new SqlConnection("Data Source=XX;Initial Catalog=DBData;User ID=sa;Password=111111"))

             {

                 conn.Open();

                 using (SqlCommand cmd = conn.CreateCommand())

                 {

                     cmd.CommandText = "select * from [DBData].[dbo].[T_Student] where Score<@Score";

                     cmd.Parameters.Add(new SqlParameter("@Score", ));

                     DataSet dataset = new DataSet();

                     //SqlDataAdapter是一个帮我们把SqlCommand查询结果填充到DataSet中的类

                     SqlDataAdapter adapter = new SqlDataAdapter(cmd);

                     adapter.Fill(dataset);

                     DataTable dt = dataset.Tables[];

                 }

             }

             MessageBox.Show("操作成功");

         }