The Moth

If you look at the form designer generated code (InitializeComponent and friends), when you add a control to your form, you'll see that the control gets created, sized, positioned etc and then finally added to the Controls collection of the form. That is all fine and necessary, what is not always necessary is having a form level field that points to the control. It is an extra 4 bytes per member and more importantly clutters the code and intellisense (and any diagrams you auto generate).

In this area, there is a small enhancement that I loved when I first saw Whidbey and I don't think it has had enough coverage, so here goes.

In Visual Studio 2005, when having a form open, you can select a control and toggle a new boolean property from the properties window (under the Design category): Generate Member. As the documentation says, it "Indicates if a member variable will be generated for this component."

So for all those projects you have upgraded, go though the controls on your forms and check to see if you are accessing the control variable outside InitializeComponent; if you are not set GenerateMember to false. For new projects make sure you remember to make that decision every time you add a control to your form; e.g. most Label instances never get accessed after you set their Text in the designer.

Note that this is not a true property, i.e. you don't get programmatic access to it of the Control class. It is simply a design-time thing done via an extender no doubt.