如何在 Swift 3 或 Swift 4 中检查互联网连接？ [复制]

Posted 2023-02-24

【中文标题】如何在 Swift 3 或 Swift 4 中检查互联网连接？ [复制]

【英文标题】：How to check internet connection in Swift 3 or Swift 4? [duplicate]

【发布时间】：2016-11-11 04:31:52

【问题描述】：

我尝试在 Swift 3 中检查互联网连接，但代码对我不起作用。

 class func isConnectedToNetwork() -> Bool 

    var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
    zeroAddress.sin_len = UInt8(MemoryLayout.size(ofValue: zeroAddress))
    zeroAddress.sin_family = sa_family_t(AF_INET)

    let defaultRouteReachability = withUnsafePointer(&zeroAddress) 
      SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0)).takeRetainedValue()
    

    var flags: SCNetworkReachabilityFlags = SCNetworkReachabilityFlags(rawValue: UInt32(0))
    if SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) == 0 
      return false
    

    let isReachable = (flags & UInt32(kSCNetworkFlagsReachable)) != 0
    let needsConnection = (flags & UInt32(kSCNetworkFlagsConnectionRequired)) != 0

    return (isReachable && !needsConnection) ? true : false
  

我还导入了 SystemConfiguration 框架。请建议如何检查。

【问题讨论】：

定义“不工作”。

您可以查看此链接以供参考。它包含连接或断开连接时的网络检查。 ***.com/questions/40066530/…

【参考方案1】：

最新的 swift3 代码

这里 检查互联网连接的最简单方法是使用 ios 可达性 API。检查此波纹管链接并下载将可达性文件添加到您的项目。您必须并且应该将系统配置框架添加到项目中

 [1]: https://github.com/ashleymills/Reachability.swift/tree/feature/ios10

完成上述工作后，只需编写此代码来检查网络连接。这里我也写了一些警告消息。

    func networkStatusChanged(_ notification: Notification) 
    let userInfo = (notification as NSNotification).userInfo
    print(userInfo!)

func interNetChecking( )   
    let status = Reach().connectionStatus()


    switch status 
    case .unknown, .offline:

        let alert = UIAlertController(title: "Check", message: "Internet Connection is Required at first time running the app to load images and videos ", preferredStyle: UIAlertControllerStyle.alert)
        alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.default, handler: nil))

        DispatchQueue.main.async(execute: 
            self.present(alert, animated: true, completion: nil)
        )


        print("Not connected")
    case .online(.wwan):
        print("Connected via WWAN")
    case .online(.wiFi):
        print("Connected via WiFi")
    

【参考方案2】：

   func isConnectedToNetwork() -> Bool 
    var zeroAddress = sockaddr_in()
    zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress))
    zeroAddress.sin_family = sa_family_t(AF_INET)
    let defaultRouteReachability = withUnsafePointer(&zeroAddress) 
        SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0))
    
    var flags = SCNetworkReachabilityFlags()
    if !SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) 
        return false
    
    let isReachable = (flags.rawValue & UInt32(kSCNetworkFlagsReachable)) != 0
    let needsConnection = (flags.rawValue & UInt32(kSCNetworkFlagsConnectionRequired)) != 0
    return (isReachable && !needsConnection)

problemstucks.com

【讨论】：

如果您连接到 wi-fi 但无法连接到互联网（打开谷歌页面），它仍然返回 true 表示可达。错了。

【参考方案3】：

在 Alamofire 的情况下

import Alamofire

// 像这样添加到您的 viewDidLoad() 或 AppDelegate 中

let reachabilityManager = NetworkReachabilityManager()
    reachabilityManager.listener =  status in

        switch status 

        case .notReachable:
            print("The network is not reachable")
            self.onInternetDisconnection()

        case .unknown :
            print("It is unknown whether the network is reachable")
            self.onInternetDisconnection() // not sure what to do for this case

        case .reachable(.ethernetOrWiFi):
            print("The network is reachable over the WiFi connection")
            self.onInternetConnection()

        case .reachable(.wwan):
            print("The network is reachable over the WWAN connection")
            self.onInternetConnection()

        
    

【讨论】：

别忘了给reachabilityManager.startListening() 打电话，否则听者根本不会被调用。这是一个有趣的链接，因为在使用此代码的模拟器上需要考虑一些事情：github.com/Alamofire/Alamofire/issues/2275