Hi

I tried to compile a simple C# program and access a Postgresql DB but I got this error in runtime (it compiled with no errors) :

[EMAIL PROTECTED] Mono]$ mcs dbaccess.cs  -r:Npgsql.dll -r:System.Data.dll
[EMAIL PROTECTED] Mono]$ mono dbaccess.exe

Unhandled Exception: System.InvalidCastException: Cannot cast from source type to destination type.
in <0x000e1> dbAccess:Main (System.String[] args)

****************

This is the code:

using System;
using System.Data;
using Npgsql;
public class dbAccess
 {
    public static void Main(string[] args)
    {
       string connectionString =
          "Server=localhost;" +
          "Database=opennms;" +
          "User ID=opennms;" +
          "Password=opennms;";
       IDbConnection dbcon;
       dbcon = new NpgsqlConnection(connectionString);
       dbcon.Open();
       IDbCommand dbcmd = dbcon.CreateCommand();
       string sql =
           "SELECT operatingsystem, nodeid " +
           "FROM assets";
       dbcmd.CommandText = sql;
       IDataReader reader = dbcmd.ExecuteReader();
       while(reader.Read()) {
            string operatingsystem = (string) reader["operatingsystem"];
            string nodeid = (string) reader["nodeid"];
            Console.WriteLine("OS: " +
                 operatingsystem + " " + nodeid);
       }
       // clean up
       reader.Close();
       reader = null;
       dbcmd.Dispose();
       dbcmd = null;
       dbcon.Close();
       dbcon = null;
    }
 }

What am I doing wrong?

Thanks!!!
--
Fabian
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