Hello and thank you very much for your reply. Firstly i have to read the article you have mentioned and then we can talk again. But i believe this
You see the expression (?<=) can be used both as lookbehind before the match and lookbehind after the match.
is the most important thing that i didn't know. Can you choose if (?<=) will be treated as before or after only ??? (i will found out after reading the article :)