php - How can I use special character (?) in URL -

i have developed website using raw php. have used special character (? , ~) in url. example: http://webdeveloperszone.com/?~=portfolio .

now, want rebuild website using wordpress or codeigniter. want keep existing link live, because google has cached links. means, have create links supports special character (? , ~).

can 1 tell me how can this?

php

string urlencode ( string $str ); string urldecode ( string $str ); 

javascript

encodeuri(uri); decodeuri(encodeuri(uri));