我想检查一下我是否可以在iOS上使用Cocoa Touch库或在macOS上使用Cocoa库连接互联网。

我想出了一个方法来做这个使用NSURL。我的方法似乎有点不可靠(因为即使谷歌也可能有一天宕机,依赖第三方似乎很糟糕),虽然如果谷歌没有响应,我可以检查其他一些网站的响应,但这似乎是浪费和不必要的应用程序开销。

- (BOOL)connectedToInternet {
    NSString *URLString = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://www.google.com"]];
    return ( URLString != NULL ) ? YES : NO;
}

是我做得不好,(更不用说stringWithContentsOfURL已弃用在iOS 3.0和macOS 10.4),如果是这样,有什么更好的方法来实现这一点?


当前回答

下载Reachability文件,https://gist.github.com/darkseed/1182373 在framework中添加CFNetwork.framework和'SystemConfiguration.framework' 导入“Reachability.h”

首先:在framework中添加CFNetwork.framework

代码:ViewController.m

- (void)viewWillAppear:(BOOL)animated
{
    Reachability *r = [Reachability reachabilityWithHostName:@"www.google.com"];
    NetworkStatus internetStatus = [r currentReachabilityStatus];

    if ((internetStatus != ReachableViaWiFi) && (internetStatus != ReachableViaWWAN))
    {
        /// Create an alert if connection doesn't work
        UIAlertView *myAlert = [[UIAlertView alloc]initWithTitle:@"No Internet Connection"   message:NSLocalizedString(@"InternetMessage", nil)delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil];
        [myAlert show];
        [myAlert release];
    }
    else
    {
         NSLog(@"INTERNET IS CONNECT");
    }
}

其他回答

创建一个AFNetworkReachabilityManager对象,并使用以下代码跟踪网络连通性

self.reachabilityManager = [AFNetworkReachabilityManager managerForDomain:@"yourDomain"];
[self.reachabilityManager startMonitoring];
[self.reachabilityManager setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
        switch (status) {
            case AFNetworkReachabilityStatusReachableViaWWAN:
            case AFNetworkReachabilityStatusReachableViaWiFi:
                break;
            case AFNetworkReachabilityStatusNotReachable:
                break;
            default:
                break;
        }
    }];

很简单的…试试下面这些步骤:

步骤1:将SystemConfiguration框架添加到项目中。


步骤2:将以下代码导入到头文件中。

#import <SystemConfiguration/SystemConfiguration.h>

第三步:使用以下方法

类型1: - (BOOL) currentNetworkStatus { [UIApplication sharedApplication].networkActivityIndicatorVisible = NO; BOOL连接; BOOL与; Const char *host = "www.apple.com"; SCNetworkReachabilityRef reachabilityreachabilitycreatewithname (NULL, host); SCNetworkReachabilityFlags旗帜; connected = SCNetworkReachabilityGetFlags(可达性,&flags); isConnected = NO; isConnected = connected && (flags & kSCNetworkFlagsReachable) && !(flags & kSCNetworkFlagsConnectionRequired); CFRelease(可达性); 返回与; }


类型2: 导入头文件:# Import "Reachability.h" (保龄球)currentNetworkStatus { 可达性*可达性=[互联网连接的可达性]; NetworkStatus NetworkStatus =[可达性currentReachabilityStatus]; 返回networkStatus !=不可访问; }


第四步:使用方法:

- (void)CheckInternet
{
    BOOL network = [self currentNetworkStatus];
    if (network)
    {
        NSLog(@"Network Available");
    }
    else
    {
        NSLog(@"No Network Available");
    }
}
- (void)viewWillAppear:(BOOL)animated
{
    NSString *URL = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://www.google.com"]];

    return (URL != NULL ) ? YES : NO;
}

或者使用Reachability类。

使用iPhone SDK有两种方法来检查网络可用性:

1. 检查“谷歌”页面是否打开。

2. 可达性类

有关更多信息,请参考Reachability (Apple Developer)。

当使用iOS 12或macOS v10.14 (Mojave)或更新版本时,您可以使用NWPathMonitor而不是史前可达性类。作为奖励,你可以很容易地检测到当前的网络连接类型:

import Network // Put this on top of your class

let monitor = NWPathMonitor()

monitor.pathUpdateHandler = { path in
    if path.status != .satisfied {
        // Not connected
    }
    else if path.usesInterfaceType(.cellular) {
        // Cellular 3/4/5g connection
    }
    else if path.usesInterfaceType(.wifi) {
        // Wi-Fi connection
    }
    else if path.usesInterfaceType(.wiredEthernet) {
        // Ethernet connection
    }
}

monitor.start(queue: DispatchQueue.global(qos: .background))

更多信息请访问:https://developer.apple.com/documentation/network/nwpathmonitor

以下是我在我的应用程序中是如何做到的:虽然200状态响应代码不能保证任何东西,但对我来说已经足够稳定了。这并不需要像NSData回答一样多的加载,因为我的只是检查HEAD响应。

银行的国际代码

func checkInternet(flag:Bool, completionHandler:(internet:Bool) -> Void)
{
    UIApplication.sharedApplication().networkActivityIndicatorVisible = true

    let url = NSURL(string: "http://www.google.com/")
    let request = NSMutableURLRequest(URL: url!)

    request.HTTPMethod = "HEAD"
    request.cachePolicy = NSURLRequestCachePolicy.ReloadIgnoringLocalAndRemoteCacheData
    request.timeoutInterval = 10.0

    NSURLConnection.sendAsynchronousRequest(request, queue:NSOperationQueue.mainQueue(), completionHandler:
    {(response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in

        UIApplication.sharedApplication().networkActivityIndicatorVisible = false

        let rsp = response as! NSHTTPURLResponse?

        completionHandler(internet:rsp?.statusCode == 200)
    })
}

func yourMethod()
{
    self.checkInternet(false, completionHandler:
    {(internet:Bool) -> Void in

        if (internet)
        {
            // "Internet" aka Google URL reachable
        }
        else
        {
            // No "Internet" aka Google URL un-reachable
        }
    })
}

objective - c代码

typedef void(^connection)(BOOL);

- (void)checkInternet:(connection)block
{
    NSURL *url = [NSURL URLWithString:@"http://www.google.com/"];
    NSMutableURLRequest *headRequest = [NSMutableURLRequest requestWithURL:url];
    headRequest.HTTPMethod = @"HEAD";

    NSURLSessionConfiguration *defaultConfigObject = [NSURLSessionConfiguration ephemeralSessionConfiguration];
    defaultConfigObject.timeoutIntervalForResource = 10.0;
    defaultConfigObject.requestCachePolicy = NSURLRequestReloadIgnoringLocalAndRemoteCacheData;

    NSURLSession *defaultSession = [NSURLSession sessionWithConfiguration:defaultConfigObject delegate:self delegateQueue: [NSOperationQueue mainQueue]];

    NSURLSessionDataTask *dataTask = [defaultSession dataTaskWithRequest:headRequest
        completionHandler:^(NSData *data, NSURLResponse *response, NSError *error)
    {
        if (!error && response)
        {
            block([(NSHTTPURLResponse *)response statusCode] == 200);
        }
    }];
    [dataTask resume];
}

- (void)yourMethod
{
    [self checkInternet:^(BOOL internet)
    {
         if (internet)
         {
             // "Internet" aka Google URL reachable
         }
         else
         {
             // No "Internet" aka Google URL un-reachable
         }
    }];
}