public static int Register(List <string> all_fields)
 {
     if (FieldsFilled(all_fields) && DataFunctions.IsUnique(all_fields[0], all_fields[4]))
     {
         Domain.User user = CreateUser(all_fields[0], all_fields[1], all_fields[2], all_fields[3], all_fields[4]);
         DataFunctions.AddUser(user);
         return(1);
     }
     else if (!FieldsFilled(all_fields))
     {
         return(0);
     }
     else
     {
         return(-1);
     }
 }