Question

This code throws a NullReferenceException when it calls ExecuteScalar:

selectedPassengerID = 0;  //SqlCommand command = GenericDataAccess.CreateCommand();   // 2nd test string connectionString = ''; SqlConnection conn;  connectionString = ConfigurationManager.     ConnectionStrings['ConnST-MHM'].ConnectionString; conn = new SqlConnection(connectionString); SqlCommand command = new SqlCommand(); command.CommandType = CommandType.StoredProcedure ; command.Connection = conn; command.CommandText = 'SearchForPassenger';  SqlParameter param;  param = command.CreateParameter(); param.ParameterName = '@name'; param.Value = pName; // Session['']; param.DbType = DbType.String; command.Parameters.Add(param);  param = command.CreateParameter(); param.ParameterName = '@flightDate'; param.Value = date;  param.DbType = DbType.String; command.Parameters.Add(param);  param = command.CreateParameter(); param.ParameterName = '@ticketNo'; param.Value = ticketNumber;  param.DbType = DbType.Int32; command.Parameters.Add(param);  int item;  command.Connection.Open(); item = (int)command.ExecuteScalar(); 

Answer 1

I have encapsulated most of my SQL logic in a DAL. One of these DAL methods pulls scalar Ints using the following logic. It may work for you:

  object temp = cmnd.ExecuteScalar();   if ((temp == null) || (temp == DBNull.Value)) return -1;   return (int)temp; 

I know that you have entered a lot of code above but I think that this is really the essence of your problem. Good luck!