How to recognize code generated by Visual Studio's GUI designer?

Question

Visual Studio is kind enough to generate a lot of code for us when we create and design Windows.Forms controls. It also surrounds most of it with a #region statement. In newer versions it also uses a partial class to separate generated from manually created code. Developers are supposed to edit code only in certain areas.

But nothing prevents us from violating this in whatever way we please. I'm fine with manual edits that could just as well have been made from the designer, or manual edits in areas the designer doesn't touch. But I'd like to flag any other kind of edit.

Does anyone know a utility that can do this? StyleCop rules perhaps? I mostly need it for the combination of C#, Windows.Forms, and Visual Studio 2003, 2005, and 2008.

Answer 1

These days, designer code should end up in a .Designer.cs file. It should be very rare that developers need to touch that. Unfortunately, I don't know any way of verifying that the code was genuinely generated by the designer. It would be handy if it included some sort of hash, but it doesn't as far as I'm aware...

Given how easy it is now to just say "don't edit designer files" do you really need another system though? It's not like you need to stay away from specific regions - it's the whole file which is out of bounds.

Answer 2

Why should developers not be allowed to change this code? If they are able to write code that works, they should be allowed to do it. If they are not able to write code that works, lets say they should be trained or fired.

You just have to extend the meaning of "it works" to "it works at runtime as well as in the designer". So what's wrong about that?

Todays gui designers are not very restrictive and are doing a good job in "understanding" code that had been written by a human.

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There is also real generated code around, for instance code generated by some xml specification, resources etc. This code is generated when building, so when it had been changed, these changes are undone whenever the application is built.

Designers are not real code generators of this kind. They are a kind of "coding helpers", helping the developer to write code faster then by typing it in. But it should actually be possible to write the same kind of code manually although limiting one self to the designers capabilities is a reasonable maintainability decision.