Question

Is there an easy way in C++ to tell if a RTF text string has any content, aside pure formatting.

For example this text is only formatting, there is no real content here:

{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fnil\fcharset0 MS Sans Serif;}}

Loading RTF text in RichTextControl is not an option, I want something that will work fast and require minimum resources.

Answer 1

The only sure-fire way is to write your own RTF parser [spec], use a library like LibRTF, or you might consider keeping a RichTextControl open and updating it with new RTF documents rather than destroying the object every time.

I believe RTF is not a regular language, so cannot be properly parsed by RegEx (not unlike HTML, despite millions of attempts to do so), but you do not need to write a complete RTF parser.
I’d start with a simple string parser. Try:

1. Remove content between {\ and }
2. Remove tags. Tags begin with a backslash, \, and are followed by some text. If a backslash is followed by whitespace, it is not a tag.
3. The document should end with at least one closing curly brace, }

Any content left which isn’t whitespace should be document content, though this may have some exceptions so you’ll want to test on numerous samples of RTF.