Question

I wanna to know ,if there’s a difference between :

IfxDataReader ifxDataReaders = ifxCommand.ExecuteReader();
                    using (ifxDataReaders)
                    {
                        if (ifxDataReaders.Read())
                        {
                            item = (int)ifxDataReaders[0];
                        }
                        ifxDataReaders.Close();
                    }

---

  using(IfxDataReader ifxDataReaders = ifxCommand.ExecuteReader())
                         {

                            if (ifxDataReaders.Read())
                            {
                                item = (int)ifxDataReaders[0];
                            }
                            ifxDataReaders.Close();

                         }

Answer 1

_{The tempting statement is to say “the first one won’t dispose”, but it will.}

_{The second tempting statement is to say “the first one won’t dispose if ExecuteReader throws an exception”, but in this case neither will dispose.}

If an error occurs in ExecuteReader, in both instances ifxDataReaders will not have been assigned so the Dispose call will never resolve anyway. As an aside, the call to Close is not actually required.

Dispose will be called in both instances and I believe in the same circumstances.

Variable scope will change. In the second instance, ifxDataReaders is scoped to the using whereas in the first ifxDataReaders can be used after the using (although, you’d be using a disposed object at this point).

The second form is preferred, to me it seems more explicit and is more readable.