Right-click on the file and select Open with...
Select CSharp Editor and click Set as Default
Then click Open

From now on double clicking a component will open it in code view.

>This is really a generic .NET question but since I'm use MM, I'll ask it here. When I create data objects, sometime I get a CS file and a RESX file and sometime I only have a CS file. I know the RESX file is the resource file for the visual components. Since the data object is obviously NOT a visual component, how do I remove the link to the RESX file so double-clicking on the file in the solution explorer will open the code instead of that empty page.