How to step into RTL/VCL?

When debugging using the Delphi 7 IDE how can I step into code in the program files/borland/delphi7/source folder?

Sounds like a dumb question, but inquiring minds want to debug. (not that I think 开发者_StackOverflow中文版anything is wrong with the source, I just want to know why for the 9000th time I can't assign a TJpegImage to a TjpegImage).

Make sure you have the "Use debug dcus" option enabled in the Project Options, and the VCL source folder is in the Debugger's Source path.

As for why you cannot assign a TJPEGImage to a TJPEGImage, that would normally only happen if you are trying to pass a TJPEGImage object across a DLL boundary without the use of runtime packages, thus the app and DLL are doing internal comparisons against different copies of the RTL, causing the is operator (ie: ASource is TJPEGImage) to return False where it would normally report True instead.

Did you added the RTL/VCL source path to debug units path? Also, my Delphi 7 asks me to provide location of source file I want to step into if it's not in the path ... so should yours do :)