The ExitCode property returns the numeric exit code for the
          command that was previously executed on the server. This property
          value is only meaningful after the command has completed and the
          connection closed by calling the Disconnect method. In most
          cases, an exit code value of zero indicates success, while any other
          value indicates an error condition.
          Note that the actual value is application dependent and is only
          meaningful in the context of that particular program. A program may
          choose to use exit codes in a non-standard way, such as having
          certain non-zero values indicate success.
          The Reset method will reset the exit code back to its
          default value of zero.