HOW TO CALCULATE TOTAL SURFACE ARE AT DRAWING MODE?
This requires a macro. I have not seen one specifically, however there used to be a file "How to calculate the surface area of a model, including reference surfaces" API on SolidWorks website at http://www.solidworks.com/pages/services/CodeExamples.html. That example has been deleted. Maybe someone out there still has it? If you know programming, you can modify it to do that.
I am attaching a text file that should help you. This is for running a macro inside an equation to drive a custom property. Instructions are included on how to use it. Just remember this was created to calculate the open area of an extrude-cut.
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