how to decode an encoded string passed through a url

[Virangya]

hi,
i encoded a long string before i sent it to a url trough javascript.
now when i display it using php $_GET[] all the text displays correctly except a "'" (single quotation) it displays as, %u2019 . i'm not sure if there are other encoding that $_get[] won't convert.. how can i decode these? appreciate your reply. thanks in advance.

http://php.net/manual/en/function.urldecode.php

[Virangya]

http://php.net/manual/en/function.urldecode.php

thank you ardav for your reply. oh i tried that before, but still output is same.