SSID全称Service Set IDentifier, 即Wifi网络的公开名称.

#import <SystemConfiguration/CaptiveNetwork.h>

- (NSString *) getSSID
{
    NSArray *ifs = (__bridge id)CNCopySupportedInterfaces();
    id info = nil;
    for (NSString *ifnam in ifs) {
        info = (__bridge id)CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam);
        if (info && [info count]) {
            break;
        }
    }
    NSDictionary *dctySSID = (NSDictionary *)info;
    NSString *SSID = [dctySSID objectForKey:@"SSID"];
    if (SSID && [SSID isKindOfClass:[NSString class]]) {
        NSString *ssid = [SSID lowercaseString];
        return ssid;
    }
    else {
        return nil;
    }
}