iOS 4.1+获取当前连接的网络信息:

#import <SystemConfiguration/CaptiveNetwork.h>

- (id)fetchSSIDInfo
{
    NSArray *ifs = (id)CNCopySupportedInterfaces();
    NSLog(@"%s: Supported interfaces: %@", __func__, ifs);
    id info = nil;
    for (NSString *ifnam in ifs) {
        info = (id)CNCopyCurrentNetworkInfo((CFStringRef)ifnam);
        NSLog(@"%s: %@ => %@", __func__, ifnam, info);
        if (info && [info count]) {
            break;
        }
        [info release];
    }
    [ifs release];
    return [info autorelease];
}

ref:

http://stackoverflow.com/questions/15195704/how-to-get-bssid-in-iphone-without-private-library

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