How do I come out of Wi-fi?

[hammersginge]

Where I work there is free wi-fi internet connection, however because it is so slow it's pointless me being on it and would rather use 3g and my internet conncetion.

Does anyone know how I can disconnect from this wi-fi zone? bare in mind that it does not ask me whether I want to join anymore, it just loads right up over wi-fi.

 

[Tallest Skil]

Turn off Wi-Fi in Preferences.

 

[soberbrain]

Forget a network, so iPhone doesn’t join it automatically:
Choose Wi-Fi and tap > next to a network you’ve joined before. Then tap “Forget this Network.”

Under Settings - Wifi from http://www.apple.com/iphone/tips/

 

[vandozza]

an alternative solution might be to go to settings-->wi-fi-->click blue button of wireless network in question (you will have to try this when near the wi-fi network!)-->then choose "forget this network"

your iphone now wont auto-connect to this network.
you might get a pop-up asking if you would like to join it again in the future, but i think it's easier than turing wi-fi on/off frequently.