[RESOLVED] Exception Issue and N-tier issue (c#)

[zero cool]

Hi,

I was required to build a N-tier system.

User -> Business -> Data -> Database
Interface <- layer <- Access <-

My question is, how do u implement the exception in the data-access-layer and show it to the user-interface layer.

The following is my code from the data-access layer in c#

public class DataAccess
{
   public string ReadData()
   {
      try
      {
         // Read data from the database
      } 
      catch (Exception e)
      {
         throw new IOException ("Could not read from database", e);
         /* I can just retun null here, but I just want to show the message to 
             the user            
         */
      }
   }
}

Thanks a lot.