iOS动态监听网络变化

首先需要导入Reachability.h ...m 2个文件，然后在init注册监听

#import "Reachability.h"

 //注册网络状态改变通知        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];        hostReach = [[Reachability reachabilityWithHostName:@"www.baidu.com"] retain];//可以以多种形式初始化        [hostReach startNotifier];  //开始监听,会启动一个run loop

-(void)reachabilityChanged:(NSNotification *)note{    NetworkStatus status = [hostReach currentReachabilityStatus];    if (status == NotReachable){        NSLog(@"网络不可用哦");        isNetworkAvalible = NO;    }else{        NSLog(@"网络可用了哦");        isNetworkAvalible = YES;        [self startMonitor];    }}

这样就可以动态监测程序内的网络变化了。