Yes, it can be done. By default, this feature is disabled. To enable "Edit" and "Continue", go to "Tools" .. "Options" in the IDE menu of the visual studio. Open the Debug section of the tree and click Modify and Continue. Make sure the "Enable editing and continued" checkbox is selected. If you are using VS 2005 Professional, you may need to click the checkbox at the bottom of this screen to say something like Show all options.

UPDATE You must be at a breakpoint in your code for editing. You cannot edit method signatures, add new methods, etc. Changes like this were not meant to be edited and continued, and I cannot even think about how this will be implemented by Microsoft.
Hottester
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