DataSet,DataTable绑定gridview

前台

<asp:Button ID="Button1" runat="server" Text="显示" onclick="Button1_Click" />
 <asp:Button ID="Button2" runat="server" onclick="Button2_Click" Text="显示1" />

后台

protected void Button1_Click(object sender, EventArgs e)
        {
            string constr=@"Data source=PC-20121107KEFI\MSAS;initial catalog=School;user id=sa;password=12345";
            string sql="select * from T_student";

            DataSet ds = new DataSet();
            SqlDataAdapter adapter= new SqlDataAdapter(sql,constr);
            adapter.Fill(ds);
            GridView1.DataSource = ds.Tables[0];
            GridView1.DataBind();
        }

        protected void Button2_Click(object sender, EventArgs e)
        {
            string constr = @"Data source=PC-20121107KEFI\MSAS;initial catalog=School;user id=sa;password=12345";
            string sql = "select * from T_student";
            DataTable dt = new DataTable();
            SqlDataAdapter adapter = new SqlDataAdapter(sql, constr);
            adapter.Fill(dt);
            GridView1.DataSource = dt;
            GridView1.DataBind();
        }