RealCasually RealCasually - 4 months ago 16
iOS Question

Easiest way to detect Internet connection on iOS?

I know this question will appear to be a dupe of many others, however, I don't feel the simple case is well explained here. Coming from an Android and BlackBerry background, making requests through

HTTPUrlConnection
instantly fail if there is no connection available. This seems like completely sane behavior, and I was surprised to find
NSURLConnection
in iOS did not emulate it.

I understand that Apple (and others who have extended it) provide a
Reachability
class to assist with determining the network state. I was happy to first see this and fully expected to see something like
bool isNetworkAvailable()
, but instead to my surprise I found a complex system requiring notification registrations and callbacks, and a bunch of seemingly unnecessary details. There must be a better way.

My app already gracefully handles connection failures, including no connectivity. The user is notified of the failure, and the app moves on.

Thus my requirements are simple: Single, synchronous function I can call before all HTTP requests to determine if I should bother actually sending the request or not. Ideally it requires no set up and just returns a boolean.

Is this really not possible on iOS?

Answer

I did a little more research and I am updating my answer with a more current solution. I am not sure if you have already looked at it but there is a nice sample code provided by Apple.

Download the sample code here

Include the Reachability.h and Reachability.m files in your project. Take a look at ReachabilityAppDelegate.m to see an example on how to determine host reachability, reachability by WiFi, by WWAN etc. For a very simply check of network reachability, you can do something like this

Reachability *networkReachability = [Reachability reachabilityForInternetConnection];   
NetworkStatus networkStatus = [networkReachability currentReachabilityStatus];    
if (networkStatus == NotReachable) {        
    NSLog(@"There IS NO internet connection");        
} else {        
     NSLog(@"There IS internet connection");        
}

@BenjaminPiette's: Don't forget to add SystemConfiguration.framework to your project.

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