Is there any API that i can distinguish between 3G Network and Wifi?

I am working with my ipad app. With 开发者_运维百科my iPad 3G,it's a trouble that i can't solve. I want to distinguish between 3G network and wifi in my app. Anyone had encountered the same problem before? any advice welcomed! Thanks!

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You want the "reachability" API that is discussed here.

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This should help:

http://www.drobnik.com/touch/2010/08/reachability/

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You can use this to distinguish 3G or WIFI network~

//For 3G check
boolean is3g = manager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE)
        .isConnectedOrConnecting();
//For WiFi Check
boolean isWifi = manager.getNetworkInfo(ConnectivityManager.TYPE_WIFI)
        .isConnectedOrConnecting();