How to expand the Macros provided by MFC in your source code ?

MFC provides number of macros to us such as RGB, DECLARE_MESSAGE_MAP, BEGIN_MESSAGE_MAP etc. If we want to see what goes inside these macros we can see the expanded code of our program. For this, Select Project menu | Settings | Link tabs. In the ‘Project Options’ edit box delete all the options and type /EP in it. Now compile the file. You will see the expanded code in the output window.