I wanted an edit that shows format characters ('TAB' and 'CR\LF'). I tried a little with an CEdit but it never worked.
The I found CRTFCtrl::GetCharPos() which will give you the coordinates of a given character in the control. With this function I was able to determin the position of the format characters I wanted to be shown.
So all I do is everytime the content of the control alters I redraw every visible format character.
The approach is very generic and can be used for other effects.
BUGs: If you drag and drop text with format characters, the selection remains (-> any help with this problem is welcome!)
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