Thanks for your reply!
1> The finnal requirement is ” The different section can apply the corresponding Configuration and the Plugin
For example: in a HTML docuemnt, it’s can’t activate the wordComplete plugin(only HTML keyword shows up, Css Keyword is missing) in style section .Autocomplete Plugin also has the same problem;

2>Nice solution! It’s works for me, but still have the cross-section problem above;

3> Sorry for misunderstanding, the “snippets titled” means:
when creating a new spippet, I can add a title/name on it, so I can recognize what the snippet means.(rather than a bunch of raw code, hard to tell which it is)
:-( :-(