To delete a container class, select the .cls file in the Project Explorer view and press Delete. You cannot delete a class via the Visual Designer, and you cannot delete the container object (the form) from the Design Canvas.
When you delete a UI .cls file, the corresponding compiled
r-code file is also deleted.
Note: For some UI classes that you create, an
accompanying RESX file of the same name is created. This file is not
automatically deleted when you delete a class file, so you should manually clean
up unneeded RESX files. By default, the Resources view does not list RESX files.
If you want to see them in the Resources view, click
, select Filters, and uncheck the
.resx entry.