Requirements

Once you have added the .h/m files to your project, simply:

• Go to the Project->TARGETS->Build Phases->Link Binary With Libraries.
• Press the plus in the lower left of the list.
• Add SystemConfiguration.framework.

Boom, you're done.

示例

一、Blocks 方法示例

使用 Blocks 塊來監(jiān)聽網(wǎng)絡(luò)狀態(tài)是否改變。該 Blocks 將會(huì)在后臺(tái)線程中被調(diào)用，因此你需要將UI 更新切換到主線程中。

Objective-C 示例

// 創(chuàng)建 reachability 對(duì)象
Reachability *reach = [Reachability reachabilityWithHostname:@"www.google.com"];

// 設(shè)置網(wǎng)絡(luò)可以訪問的 blocks 回調(diào)
reach.reachableBlock = ^(Reachability*reach)
{
    // 記住這里的代碼會(huì)在后臺(tái)線程中被調(diào)用，如果你想要更新 UI，一定到切換到主線程：
    dispatch_async(dispatch_get_main_queue(), ^{
        NSLog(@"REACHABLE!");
    });
};

// 設(shè)置網(wǎng)絡(luò)不可訪問的 blocks 回調(diào)
reach.unreachableBlock = ^(Reachability*reach)
{
    NSLog(@"UNREACHABLE!");
};

// 開啟監(jiān)聽
[reach startNotifier];

Swift 3 示例

import Reachability

var reach: Reachability?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Allocate a reachability object
        self.reach = Reachability.forInternetConnection()
        
        // Set the blocks
        self.reach!.reachableBlock = {
            (reach: Reachability?) -> Void in
            
            // keep in mind this is called on a background thread
            // and if you are updating the UI it needs to happen
            // on the main thread, like this:
            DispatchQueue.main.async {
                print("REACHABLE!")
            }
        }
        
        self.reach!.unreachableBlock = {
            (reach: Reachability?) -> Void in
            print("UNREACHABLE!")
        }
        
        self.reach!.startNotifier()
    
        return true
}

二、NSNotification 通知方法示例

此示例將使用 NSNotification 來通知網(wǎng)絡(luò)連接狀態(tài)的變化。 它們將在主線程上被調(diào)用，因此你可以從該函數(shù)內(nèi)部進(jìn)行UI更新。

此外，它要求Reachability對(duì)象默認(rèn)將 WWAN（3G / EDGE / CDMA）蜂窩網(wǎng)絡(luò)視為不可達(dá)的連接（如果你正在編寫視頻流應(yīng)用程序（例如，用于保存用戶的數(shù)據(jù)計(jì)劃），則可以使用此功能）。

Objective-C 示例

// 通過指定域名的方式創(chuàng)建 reachability 對(duì)象
Reachability* reach = [Reachability reachabilityWithHostname:@"www.google.com"];

// 不判斷蜂窩網(wǎng)絡(luò)是否可用
reach.reachableOnWWAN = NO;

// Here we set up a NSNotification observer. The Reachability that caused the notification
// is passed in the object parameter
[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(reachabilityChanged:)
                                             name:kReachabilityChangedNotification
                                           object:nil];

[reach startNotifier];

接收通知的方法：

-(void)reachabilityChanged:(NSNotification*)note
{
    Reachability * reach = [note object];
    if([reach isReachable])
    {
        NSString * temp = [NSString stringWithFormat:@"GOOGLE Notification Says Reachable(%@)", reach.currentReachabilityString];
        NSLog(@"%@", temp);
    }
    else
    {
        NSString * temp = [NSString stringWithFormat:@"GOOGLE Notification Says Unreachable(%@)", reach.currentReachabilityString];
        NSLog(@"%@", temp);
    }
}

Swift 3 示例

import Reachability

var reach: Reachability?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    // Allocate a reachability object
    self.reach = Reachability.forInternetConnection()
    
    // Tell the reachability that we DON'T want to be reachable on 3G/EDGE/CDMA
    self.reach!.reachableOnWWAN = false
    
    // Here we set up a NSNotification observer. The Reachability that caused the notification
    // is passed in the object parameter
    NotificationCenter.default.addObserver(
        self,
        selector: #selector(reachabilityChanged),
        name: NSNotification.Name.reachabilityChanged,
        object: nil
    )
    
    self.reach!.startNotifier()
    
    return true
}
        
func reachabilityChanged(notification: NSNotification) {
    if self.reach!.isReachableViaWiFi() || self.reach!.isReachableViaWWAN() {
        print("Service avalaible!!!")
    } else {
        print("No service avalaible!!!")
    }
}

Tell the world

Head over to Projects using Reachability and add your project for "Maximum Wins!".

總結(jié)

1. 創(chuàng)建 Reachability 對(duì)象的方法有以下幾種：

+(instancetype)reachabilityWithHostName:(NSString*)hostname; // 指定域名
+(instancetype)reachabilityForInternetConnection; // 通用網(wǎng)絡(luò)連接
+(instancetype)reachabilityWithAddress:(void *)hostAddress; // 指定地址
+(instancetype)reachabilityForLocalWiFi; // 指定Wi-Fi網(wǎng)絡(luò)

2. 可選設(shè)置，是否忽視蜂窩網(wǎng)絡(luò)可達(dá)性

@property (nonatomic, assign) BOOL reachableOnWWAN;

3. 監(jiān)聽網(wǎng)絡(luò)可達(dá)性的方法有兩種：

Blocks 方式：

@property (nonatomic, copy) NetworkReachable    reachableBlock;
@property (nonatomic, copy) NetworkUnreachable  unreachableBlock;

通知方式：

[[NSNotificationCenter defaultCenter] addObserver:self 
                                        selector:@selector(reachabilityChanged:) 
                                            name:kReachabilityChangedNotification 
                                          object:nil];

4. 開始、停止監(jiān)聽

-(BOOL)startNotifier;
-(void)stopNotifier;

示例代碼

// 網(wǎng)絡(luò)可達(dá)性檢查
Reachability *reachability = [Reachability reachabilityWithHostName:URL_HOST];
reachability.reachableBlock = ^(Reachability *reachability) {
    // 3.0s 后執(zhí)行加載任務(wù)
    // 默認(rèn)情況下，切換到主線程更新UI，這里延遲3秒是為了多旋轉(zhuǎn)一會(huì)菊花用的。
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        // 連接服務(wù)器
        [self connectToServer];
    });
};
reachability.unreachableBlock = ^(Reachability *reachability) {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        self.emptyDescription = @"無法訪問服務(wù)器，請(qǐng)稍后再試。";
        self.displayEmptyDataSet = YES;
        self.loading = NO;
    });
};
[reachability startNotifier];

類似框架

1. Apple 官方示例：Reachability
2. AFNetworking 的 AFNetworkReachabilityManager 類