how to check gprs connectivity on iphone 4

in my app i want to check the gprs connectivity on iphone if gprs not present then i have to send sms so how can i do that please tell me

Than开发者_如何学Pythonks in advance

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There's a sample application from Apple, showing how you can check the connectivity of an iOS device. The code is available here: http://developer.apple.com/library/ios/#samplecode/Reachability/Introduction/Intro.html