Try the snippet below, you may need to research some of the other classes to get your connectionString (DSN= etc), but this worked for me.
public static void ReadData(string connectionString)
string queryString = "SELECT count(*) from INV";
using (OdbcConnection connection = new OdbcConnection(connectionString))
OdbcCommand command = new OdbcCommand(queryString, connection);
// Execute the DataReader and access the data.
OdbcDataReader reader = command.ExecuteReader();
// Call Close when done reading.