using (SqlConnection conn = new SqlConnection("server=(local);database=Northwind;user id=sa;password=sa;"))
{
    //在InfoMessage事件中获取print值
    conn.InfoMessage += delegate(object sender1, SqlInfoMessageEventArgs e1) { Response.Write(e1.Message); };

    conn.Open();
    using (SqlCommand cmd = new SqlCommand("update Products set ProductName='aaa' where ProductID=0; print @@rowcount;print 11+12;", conn))
    {
        cmd.ExecuteNonQuery();
    }
    conn.Close();
}