Is there an extension for Visual Studio 2010 for opening code for forms, components etc. in WinForms application projects on double click in solution explorer by default (and in designer view via context menu)?
item -> right click -> Open With -> Source Code (Text) Editor -> press Set as Default button
you can set visual studio's default editor to be the code view rather than the form view. Just right-click and choose Open With... then you can set the default in there.
You can press F7 to toggle between designer and code.
Not sure about double click, but if you select the file in Project Explorer (ex: Form1.cs) and press F7 you see the code.
来源：https://stackoverflow.com/questions/7037905/how-to-open-code-on-double-cick-on-form-by-default