(1). 下载 https://developer.apple.com/library/ios/samplecode/Reachability/Reachability.zip
(2). 拖reachability.h，reachability.m入工程 (库非ARC)
ARC:-fno-objc-arc
(3) .导入SystemConfiguration.framework
(4).用法
复制代码 代码如下:
-(NSString*)getNetType
{
NSString* result;
Reachability *r = [Reachability reachabilityWithHostName:@"www.baidu.com"];
NSLog(@" ====:%i",[r currentReachabilityStatus]);
switch ([r currentReachabilityStatus]) {
case NotReachable:// 没有网络连接
result=@"没有网络连接";
break;
case ReachableViaWWAN:// 使用3G网络
result=@"3g";
break;
case ReachableViaWiFi:// 使用WiFi网络
result=@"wifi";
break;
}
NSLog(@"caseReachableViaWWAN=%i",ReachableViaWWAN);
NSLog(@"caseReachableViaWiFi=%i",ReachableViaWiFi);
return result;
}
(5)如果无法区分出2G、2.5G、3G网络的区别，那么我们可以将Reachability.m中的networkStatusForFlags方法重构：
复制代码 代码如下:
- (NetworkStatus) networkStatusForFlags: (SCNetworkReachabilityFlags) flags
{
if ((flags & kSCNetworkReachabilityFlagsReachable) == 0)
{
return NotReachable;
}
BOOL retVal = NotReachable;
if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0)
{
// if target host is reachable and no connection is required
// then we'll assume (for now) that your on Wi-Fi
retVal = 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
retVal = ReachableViaWiFi;
}
}
if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN)
{
if((flags & kSCNetworkReachabilityFlagsReachable) == kSCNetworkReachabilityFlagsReachable) {
if ((flags & kSCNetworkReachabilityFlagsTransientConnection) == kSCNetworkReachabilityFlagsTransientConnection) {
retVal = ReachableVia3G;
if((flags & kSCNetworkReachabilityFlagsConnectionRequired) == kSCNetworkReachabilityFlagsConnectionRequired) {
retVal = ReachableVia2G;
}
}
}
}
return retVal;
}
//检查当前网络连接是否正常
-(BOOL)connectedToNetWork
{
struct sockaddr_in zeroAddress;
bzero(&zeroAddress, sizeof(zeroAddress));
zeroAddress.sin_len = sizeof(zeroAddress);
zeroAddress.sin_family = AF_INET;
SCNetworkReachabilityRef defaultRouteReachability = SCNetworkReachabilityCreateWithAddress(NULL, (struct sockaddr *)&zeroAddress);
SCNetworkReachabilityFlags flags;
BOOL didRetrieveFlags = SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags);
CFRelease(defaultRouteReachability);
if (!didRetrieveFlags) {
printf("Error. Count not recover network reachability flagsn");
return NO;
}
BOOL isReachable = flags & kSCNetworkFlagsReachable;
BOOL needsConnection = flags & kSCNetworkFlagsConnectionRequired;
return (isReachable && !needsConnection) ? YES : NO;
}
//检查网络连接类型
-(void)checkNetworktype:(id)sender{
NSString *connectionKind;
if ([self connectedToNetWork]) {
hostReach = [Reachability reachabilityWithHostName:@"www.google.com"];
switch ([hostReach currentReachabilityStatus]) {
case NotReachable:
connectionKind = @"没有网络链接";
break;
case ReachableViaWiFi:
connectionKind = @"当前使用的网络类型是WIFI";
break;
case ReachableVia3G:
connectionKind = @"当前使用的网络链接类型是WWAN（3G）";
break;
case ReachableVia2G:
connectionKind = @"当前使用的网络链接类型是WWAN（2G）";
break;
default:
break;
}
}else {
connectionKind = @"没有网络链接";
}
}