@interface Reachability : NSObject
/*!
* Use to check the reachability of a given host name.
*/
+ (instancetype)reachabilityWithHostName:(NSString *)hostName;
/*!
* Use to check the reachability of a given IP address.
*/
+ (instancetype)reachabilityWithAddress:(const struct sockaddr_in *)hostAddress;
/*!
* Checks whether the default route is available. Should be used by applications that do not connect to a particular host.
*/
+ (instancetype)reachabilityForInternetConnection;
/*!
* Checks whether a local WiFi connection is available.
*/
+ (instancetype)reachabilityForLocalWiFi;
/*!
* Start listening for reachability notifications on the current run loop.
*/
- (BOOL)startNotifier;
- (void)stopNotifier;
- (NetworkStatus)currentReachabilityStatus;
/*!
* WWAN may be available, but not active until a connection has been established. WiFi may require a connection for VPN on Demand.
*/
- (BOOL)connectionRequired;
@end
static void ReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void* info)
{
#pragma unused (target, flags)
NSCAssert(info != NULL, @"info was NULL in ReachabilityCallback");
NSCAssert([(__bridge NSObject*) info isKindOfClass: [Reachability class]], @"info was wrong class in ReachabilityCallback");
//http://www.cnblogs.com/xiaofeixiang
Reachability* noteObject = (__bridge Reachability *)info;
// Post a notification to notify the client that the network reachability changed.
[[NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject];
}
- (NetworkStatus)networkStatusForFlags:(SCNetworkReachabilityFlags)flags
{
PrintReachabilityFlags(flags, "networkStatusForFlags");
if ((flags & kSCNetworkReachabilityFlagsReachable) == 0)
{
// The target host is not reachable.
return NotReachable;
}
NetworkStatus returnValue = NotReachable;
if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0)
{
/*
If the target host is reachable and no connection is required then we'll assume (for now) that you're on Wi-Fi...
*/
returnValue = ReachableViaWiFi;
}
if ((((flags & kSCNetworkReachabilityFlagsConnectionOnDemand ) != 0) ||
(flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) != 0))
{
/*
... and the connection is on-demand (or on-traffic) if the calling application is using the CFSocketStream or higher APIs...
*/
if ((flags & kSCNetworkReachabilityFlagsInterventionRequired) == 0)
{
/*
... and no [user] intervention is needed...
*/
returnValue = ReachableViaWiFi;
}
}
if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN)
{
/*
... but WWAN connections are OK if the calling application is using the CFNetwork APIs.
*/
returnValue = ReachableViaWWAN;
}
return returnValue;
}
- (BOOL)connectionRequired
{
NSAssert(_reachabilityRef != NULL, @"connectionRequired called with NULL reachabilityRef");
SCNetworkReachabilityFlags flags;
if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags))
{
return (flags & kSCNetworkReachabilityFlagsConnectionRequired);
}
return NO;
}
//获取当前网络状态
- (NetworkStatus)currentReachabilityStatus
{
NSAssert(_reachabilityRef != NULL, @"currentNetworkStatus called with NULL SCNetworkReachabilityRef");
NetworkStatus returnValue = NotReachable;
SCNetworkReachabilityFlags flags;
if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags))
{
if (_alwaysReturnLocalWiFiStatus)
{
returnValue = [self localWiFiStatusForFlags:flags];
}
else
{
returnValue = [self networkStatusForFlags:flags];
}
}
return returnValue;
}