If your phone works in Europe, it'll work in China. Just make sure it's unlocked and can accept third party SIM card.

Bring it to China, buy a local mobile number, usually 5 star hotels will sell it in their business center for RMB$120 which includes RMB100 of time. Also, at airport (at least in Beijing, can't recall seeing in Shanghai but ask) you can get SIM card.

It will work IDD, local, etc. and you can buy top off cards in RMB$100 denominations. Number is good for at least 6 months, once you start topping off, it will extend to 12+ months.

Make sure you get number that is good nation-wide and not just shanghai. I know Shangrila Hotel business center used to have it.