首先在AppDelegate.h添加头文件"Reachability.h",导入框架SystemConfiguration.frame
下面是代码:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//开启网络状况的监听
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];
self.hostReach = [Reachability reachabilityWithHostName:@"www.baidu.com"] ;
//开始监听,会启动一个run loop
[self.hostReach startNotifier];
}
-(void)reachabilityChanged:(NSNotification *)note
{
Reachability *currReach = [note object];
NSParameterAssert([currReach isKindOfClass:[Reachability class]]);
//对连接改变做出响应处理动作
NetworkStatus status = [currReach currentReachabilityStatus];
//如果没有连接到网络就弹出提醒实况
self.isReachable = YES;
if(status == NotReachable)
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"网络连接异常" message:nil delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil];
[alert show];
[alert release];
self.isReachable = NO;
return;
}
if (status==kReachableViaWiFi||status==kReachableViaWWAN) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"网络连接信息" message:@"网络连接正常" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil];
// [alert show];
[alert release];
self.isReachable = YES;
}
}
然后在每个页面的viewWillAppear:加上:
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:YES];
AppDelegate *appDlg = (AppDelegate *)[[UIApplication sharedApplication] delegate];
if(appDlg.isReachable)
{
NSLog(@"网络已连接");//执行网络正常时的代码
}
else
{
NSLog(@"网络连接异常");//执行网络异常时的代码
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"网络连接异常" message:nil delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil];
[alert show];
[alert release];
}
}
这样就可以检查到在运行程序时网络突然的中断和连接。