Most bank card here link with CPlus (look at the
back of your card), so you can withdraw local
currency with that card. You need to find ABMs
support CPlus, there are a lot in big cities in
China like Shanghai, Beijing ...
I am not sure the rate, you also subject to a fee
every withdraw (1 CAD$).
If you have time, prepare some Travel Cheque is
also good. I believe it always have the better rate.