Is there any need to close a DbConnection if a using clause is used? [duplicate]

Question

Possible Duplicate:
Will a using block close a database connection?

Is db.Close() unnecessary in the following?

using (DbConnection db = GetDbConnection())
{
   // do data-access stuff
   // ...

   db.Close();
}

Answer 1

Is there any need to close a DbConnection if a using clause is used?

No, there is no need to close a DbConnection if a using clause is used?

and

Yes it is unnecessary in here because when scope of using ends, connection will dispose meaning closing and releasing all memory.

Since DBConnection implements IDisposable interface, close function is there in the Dispose method of DBConnection.

But if some lines are after close line then it is useful

using (DbConnection db = GetDbConnection())
{
  // do data-access stuff
  // ...

  db.Close(); //Useless
}

But here it is useful

using (DbConnection db = GetDbConnection())
{
  // do data-access stuff
  // ...

  db.Close(); //Useful

 // Some more code
}

In that case you can do

using (DbConnection db = GetDbConnection())
{
  // do data-access stuff
  // ...

}

// Some more code which was previously inside using section.

Answer 2

Just to be sure i have checked the code :)

   protected override void Dispose(bool disposing)
    {
      if (disposing)
      {
        this._userConnectionOptions = (DbConnectionOptions) null;
        this._poolGroup = (DbConnectionPoolGroup) null;
        this.Close();
      }
      this.DisposeMe(disposing);
      base.Dispose(disposing);
    }

This is the implementation of SqlConnection which is inheriting from DbConnection. As you can see there is this.Close() method :)

Answer 3

For what I know, when Dispose() method is called, Close() is automatically performed.
So db.Close(); is not necessary here.