title: How can i make the sum and show it?
body: <p>Why isn't the third command working?
  It is supposed to make the sum of the prices and show in the website page.</p>
  
  <pre><code>liga.Open();
  SqlCommand comando = new SqlCommand();
  comando.CommandText = "select count (*) from M16_Tbl_Cart where ID_User=" + Session["IDuser"] + "";
  comando.Connection = liga;
  int numProd = (int)comando.ExecuteScalar();
  comando.CommandText = "SELECT Image, Name, Size, Price FROM dbo.M16_Tbl_Cart where ID_User="+Session["IDuser"]+"";
  comando.Connection = liga;
  comando.CommandText = "SELECT sum(Price) as PriceSum from M16_Tbl_Cart where ID_User=" + Session["IDuser"] + "";
  comando.Connection = liga;
  SqlDataReader dataReader = comando.ExecuteReader();
  </code></pre>