使用之前请从Apple网站下载示例:点击进入下载
然后将Reachability.h 和 Reachability.m 加到自己的项目中,并引用 SystemConfiguration.framework,就可以使用了。
Reachability 中定义了3种网络状态:
// the network state of the device for Reachability 1.5. typedef enum { NotReachable = 0, //无连接 ReachableViaCarrierDataNetwork, //使用3G/GPRS网络 ReachableViaWiFiNetwork //使用WiFi网络 } NetworkStatus; // the network state of the device for Reachability 2.0. typedef enum { NotReachable = 0, //无连接 ReachableViaWiFi, //使用3G/GPRS网络 ReachableViaWWAN //使用WiFi网络 } NetworkStatus;比如检测某一特定站点的接续状况,可以使用下面的代码:
Reachability *r = [Reachability reachabilityWithHostName:@“www.apple.com”]; switch ([r currentReachabilityStatus]) { case NotReachable: // 没有网络连接 { UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"无可用网络" message:@"请先设置可用网络" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil]; [alertView show]; } break; case ReachableViaWWAN: // 使用3G网络 break; case ReachableViaWiFi: // 使用WiFi网络 break; }检测当前网络环境:
// 是否wifi + (BOOL) IsEnableWIFI { return ([[Reachability reachabilityForLocalWiFi] currentReachabilityStatus] != NotReachable); } // 是否3G + (BOOL) IsEnable3G { return ([[Reachability reachabilityForInternetConnection] currentReachabilityStatus] != NotReachable); }
连接状态实时通知
网络连接状态的实时检查,通知在网络应用中也是十分必要的。接续状态发生变化时,需要及时地通知用户。由于Reachability1.5版与2.0版有一些变化,这里分开来说明使用方法。
// My.AppDelegate.h #import "Reachability.h" @interface MyAppDelegate : NSObject <UIApplicationDelegate> { NetworkStatus remoteHostStatus; } @property NetworkStatus remoteHostStatus; @end // My.AppDelegate.m #import "MyAppDelegate.h" @implementation MyAppDelegate @synthesize remoteHostStatus; // 更新网络状态 - (void)updateStatus { self.remoteHostStatus = [[Reachability sharedReachability] remoteHostStatus]; } // 通知网络状态 - (void)reachabilityChanged:(NSNotification *)note { [self updateStatus]; if (self.remoteHostStatus == NotReachable) { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"AppName", nil) message:NSLocalizedString(@"NotReachable", nil) delegate:nil cancelButtonTitle:@"OK" otherButtonTitles: nil]; [alert show]; [alert release]; } } // 程序启动器,启动网络监视 - (void)applicationDidFinishLaunching:(UIApplication *)application { // 设置网络检测的站点 [[Reachability sharedReachability] setHostName:@"www.apple.com"]; [[Reachability sharedReachability] setNetworkStatusNotificationsEnabled:YES]; // 设置网络状态变化时的通知函数 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:@"kNetworkReachabilityChangedNotification" object:nil]; [self updateStatus]; } - (void)dealloc { // 删除通知对象 [[NSNotificationCenter defaultCenter] removeObserver:self]; [window release]; [super dealloc]; }
// MyAppDelegate.h @class Reachability; @interface MyAppDelegate : NSObject <UIApplicationDelegate> { Reachability *hostReach; } @end // MyAppDelegate.m - (void)reachabilityChanged:(NSNotification *)note { Reachability* curReach = [note object]; NSParameterAssert([curReach isKindOfClass: [Reachability class]]); NetworkStatus status = [curReach currentReachabilityStatus]; if (status == NotReachable) { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"AppName"" message:@"NotReachable" delegate:nil cancelButtonTitle:@"YES" otherButtonTitles:nil]; [alert show]; [alert release]; } } - (void)applicationDidFinishLaunching:(UIApplication *)application { // ... // 监测网络情况 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name: kReachabilityChangedNotification object: nil]; hostReach = [[Reachability reachabilityWithHostName:@"www.google.com"] retain]; [hostReach startNotifer]; // ... }
原文地址:http://blog.csdn.net/mhtios/article/details/40039123