Display data in aspx page in asp.net

SqlConnection con = new SqlConnection(@"your connection string");

    SqlCommand cmd;

    SqlDataReader rd;

    protected void Page_Load(object sender, EventArgs e)

    {

    }

    protected void Button1_Click(object sender, EventArgs e)

    {

        cmd = new SqlCommand("select * from std", con);

        con.Open();

        rd = cmd.ExecuteReader();

        if (rd.HasRows)

        {

            while (rd.Read())

            {

                Response.Write(rd["fieldname1"].ToString() + "  " + rd["fieldname2"].ToString() + "  " + rd["lname"].ToString()+"<br>");

            }

            con.Close();

        }

    }