using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; using System.Data.SqlClient; namespace ADONET基础 {     /// <summary>     /// Window1.xaml 的交互逻辑     /// </summary>     public partial class Window1 : Window     {         public Window1()         {             InitializeComponent();         }         private void button1_Click(object sender, RoutedEventArgs e)         {             ////using() 自动关闭数据库，回收资源。             ////SqlConnection为建立和数据库连接的对象。             //using (SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=myself;User Id=sa;Password=123;"))             //{             //    conn.Open();//打开连接             //    //通过连接，创建一个向数据库发命令的对象SqlCommand             //    using (SqlCommand cmd = conn.CreateCommand())//释放资源。             //    {             //        //CommandText为要执行的SQL的语句             //        cmd.CommandText = "Insert into student(学号,姓名) values(110,'张五')";             //        //ExecuteNonQuery一般用来执行Update Delete Insert 语句。             //        cmd.ExecuteNonQuery();//执行上面的SQL语句。             //    }             //}             using (SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=MyTest;User Id=sa;Password=123;"))             {                 conn.Open();                 using (SqlCommand cmd = conn.CreateCommand())                 {                     //cmd.CommandText = "select count(*) from student where 入学成绩<570";                     //cmd.CommandText = "select count(*) from student where 入学成绩<570";                     ////ExecuteScalar一般用来执行有且只有一行一列返回值的SQL语句。                     //int i = (int)cmd.ExecuteScalar();                     //MessageBox.Show(i+"人成绩小于570分");                     cmd.CommandText = "Insert into T_Student(Name,Age) output inserted.Id values('张顾',18);";                     long i = (long)cmd.ExecuteScalar();                     MessageBox.Show("Id为"+i);                 }             }             MessageBox.Show("执行完成");         }     } }