IOS检测网络连接状态(转)

梦里梦外; 2022-03-11 03:56 306阅读 0赞

使用之前请从Apple网站下载示例：[点此下载][Link 1]

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];
        // ...
    }

[Link 1]: https://developer.apple.com/library/ios/samplecode/Reachability/Reachability.zip