IOS检测网络连接状态(转)

IOS检测网络连接状态(转)

使用之前请从Apple网站下载示例：点此下载

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 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。

Reachability 1.5

// 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];
}

Reachability 2.0

// 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]; // ... }