Ado.net连接数据库查询表信息的多种方法

         // 第一种方法

            /*string str = "server = . ; database = booksdata ; user id = sa ; pwd = sa";
            string strcom = "SELECT * FROM dbo.Books";
            SqlConnection sqlcon = new SqlConnection(str);
            SqlCommand  sqlcom = new SqlCommand(strcom);
            sqlcom.Connection = sqlcon;
           SqlDataAdapter sda = new SqlDataAdapter(sqlcom);
           DataSet ds = new DataSet();
            sda.Fill(ds, "数据信息");
            dataGridView1.DataSource = ds.Tables[0];*/

            //  第二种方法 

            /* string str = "server = . ; database = booksdata ; user id = sa ; pwd = sa";
            SqlConnection sqlcon = new SqlConnection(str);
            string strcom = "SELECT * FROM dbo.Books";
            SqlCommand sqlcom = new SqlCommand(strcom, sqlcon);
            SqlDataAdapter sda = new SqlDataAdapter(sqlcom);
            DataSet ds = new DataSet();
            sda.Fill(ds, "数据信息");
            dataGridView1.DataSource = ds.Tables[0];*/

            //  第三种方法

           /* string str = "server = . ; database = booksdata ; user id = sa ; pwd = sa";
            string strcom = "SELECT * FROM dbo.Books";
            SqlDataAdapter sda = new SqlDataAdapter(strcom,str);
            DataSet ds = new DataSet();
            sda.Fill(ds, "数据信息");
            dataGridView1.DataSource = ds.Tables[0];*/

            //  第四种方法

          /*  string str = "server = . ; database = booksdata ; user id = sa ; pwd = sa";
            string strcom = "SELECT * FROM dbo.Books";
            SqlDataAdapter  sda = new SqlDataAdapter(strcom,str);
            DataTable dt = new DataTable("数据信息");
            sda.Fill(dt);
            dataGridView1.DataSource = dt;*/

 

            //使用dataGridView 读取数据信息

            string str = "server = . ; database = booksdata ; user id = sa ; pwd = sa";
            string strcom = "SELECT * FROM dbo.Books";
            SqlDataAdapter sda = new SqlDataAdapter(strcom, str);
            DataSet ds = new DataSet();
            DataView dv = new DataView();
            sda.Fill(ds, "数据信息");
            dv.Table = ds.Tables[0];
            dataGridView1.DataSource = dv;
            dv.Sort = " price Desc";
            dv.RowFilter = "price > 90";

 

最终查询效果图如下：