Check internet connection (iOS 10)

Question

For iOS 9 I was using Reachability public class to check wether the device is connected to the internet or not. I converted my Swift 2 code to Swift 3, and the Reachability doesn't work anymore. Can someone tell me how to check the internet connection on iOS 10? Thanks! Here's the code snippet:

open class Reachability {
    class func isConnectedToNetwork() -> Bool {
        var zeroAddress = sockaddr_in()
        zeroAddress.sin_len = UInt8(MemoryLayout.size(ofValue: zeroAddress))
        zeroAddress.sin_family = sa_family_t(AF_INET)
        let defaultRouteReachability = withUnsafePointer(to: &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)
    }
}

Answer 1

Swift 4 / Xcode 10:

I would combine two functions ( with a bit changes) are taken from the solutions by @Pavle Mijatovic and @Krutagn Patel (with thanks) to answer @Lance Samaria question. :)

I almost checked all the possibilities. (the code can be enhanced, but it works fine)

have a class as below:

import Foundation
import SystemConfiguration

public class ConnectionCheck {

    class func isConnectedToNetwork() -> Bool {

        var zeroAddress = sockaddr_in()
        zeroAddress.sin_len = UInt8(MemoryLayout<sockaddr_in>.size)
        zeroAddress.sin_family = sa_family_t(AF_INET)

        guard let defaultRouteReachability = withUnsafePointer(to: &zeroAddress, {
            $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {
                SCNetworkReachabilityCreateWithAddress(nil, $0)
            }
        }) else {
            return false
        }

        var flags: SCNetworkReachabilityFlags = []
        if !SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) {
            return false
        }

        let isReachable = flags.contains(.reachable)
        let needsConnection = flags.contains(.connectionRequired)

        return (isReachable && !needsConnection)
    }


    class func isInternetAvailable(webSiteToPing: String?, completionHandler: @escaping (_ b: Bool) -> Void) {

        // 1. Check the WiFi Connection
        guard isConnectedToNetwork() else {
            completionHandler(false)
            return
        }

        // 2. Check the Internet Connection
        var webAddress = "https://www.google.com" // Default Web Site
        if let _ = webSiteToPing {
            webAddress = webSiteToPing!
        }

        guard let url = URL(string: webAddress) else {
            completionHandler(false)
            print("could not create url from: \(webAddress)")
            return
        }

        let urlRequest = URLRequest(url: url)
        let session = URLSession.shared
        let task = session.dataTask(with: urlRequest, completionHandler: { (data, response, error) in
            if error != nil || response == nil {
                completionHandler(false)
            } else {
                completionHandler(true)
            }
        })

        task.resume()
    }
}

use the below code where you need to check the Internet connection: for example, in appDelegate -> applicationDidBecomeActive function.

explanation: whenever completionHandler function (above) is called, the result (true or false) is passed to the below code as b. so if b is true you have the Internet connection.

let web : String? = "https://www.google.com"
ConnectionCheck.isInternetAvailable(webSiteToPing: web) { (b)  in
 print(b)
if b {
print("connected") // or do something here
    } else {
print("disconnected") // or do something here
}
}

Answer 2

Try this, it works for me first import the SystemConfiguration to your class.

import SystemConfiguration

And now implement bellow function.

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(to: &zeroAddress) {
        $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {zeroSockAddress in
            SCNetworkReachabilityCreateWithAddress(nil, zeroSockAddress)
        }
    }

    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)

}

Answer 3

step 1 : create a swift file in your project. i created "ConnectionCheck.swift"

step 2 : add this code in your "ConnectionCheck.swift" file and "import SystemConfiguration" file to your "ConnectionCheck.swift" and "ViewController.swift"

import Foundation
import SystemConfiguration
public class ConnectionCheck {

class func isConnectedToNetwork() -> Bool {

    var zeroAddress = sockaddr_in()
    zeroAddress.sin_len = UInt8(MemoryLayout<sockaddr_in>.size)
    zeroAddress.sin_family = sa_family_t(AF_INET)

    guard let defaultRouteReachability = withUnsafePointer(to: &zeroAddress, {
        $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {
            SCNetworkReachabilityCreateWithAddress(nil, $0)
        }
    }) else {
        return false
    }

    var flags: SCNetworkReachabilityFlags = []
    if !SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) {
        return false
    }

    let isReachable = flags.contains(.reachable)
    let needsConnection = flags.contains(.connectionRequired)

    return (isReachable && !needsConnection)
}

}

step 3 : Now in "ViewController.swift" use this code to check Network Reachability

if ConnectionCheck.isConnectedToNetwork() {
        print("Connected")
    }
    else{
        print("disConnected")
    }

Answer 4

import Foundation
import SystemConfiguration

func isInternetAvailable() -> Bool
    {
        var zeroAddress = sockaddr_in()
        zeroAddress.sin_len = UInt8(MemoryLayout.size(ofValue: zeroAddress))
        zeroAddress.sin_family = sa_family_t(AF_INET)

        let defaultRouteReachability = withUnsafePointer(to: &zeroAddress) {
            $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {zeroSockAddress in
                SCNetworkReachabilityCreateWithAddress(nil, zeroSockAddress)
            }
        }

        var flags = SCNetworkReachabilityFlags()
        if !SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) {
            return false
        }
        let isReachable = flags.contains(.reachable)
        let needsConnection = flags.contains(.connectionRequired)
        return (isReachable && !needsConnection)
    }

This works in iOS 10

Answer 5

Here is Swift 3 solution via callback function, isConnectedToNetwork() is taken from the solution by Yasin Ugurlu from above.

class func isInternetAvailable(webSiteToPing: String?, completionHandler: @escaping (Bool) -> Void) {

    // 1. Check the WiFi Connection
    guard isConnectedToNetwork() else {
      completionHandler(false)
      return
    }

    // 2. Check the Internet Connection
    var webAddress = "https://www.google.com" // Default Web Site
    if let _ = webSiteToPing {
      webAddress = webSiteToPing!
    }

    guard let url = URL(string: webAddress) else {
      completionHandler(false)
      print("could not create url from: \(webAddress)")
      return
    }

    let urlRequest = URLRequest(url: url)
    let session = URLSession.shared
    let task = session.dataTask(with: urlRequest, completionHandler: { (data, response, error) in
      if error != nil || response == nil {
        completionHandler(false)
      } else {
        completionHandler(true)
      }
    })

    task.resume()
  }

Answer 6

1) Create a new Swift file within your project, name it “Reachability.swift”.

2) Cut & paste the following code into it to create your class.

import Foundation
import SystemConfiguration

public class Reachability {

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(sizeofValue(zeroAddress))
    zeroAddress.sin_family = sa_family_t(AF_INET)

    let defaultRouteReachability = withUnsafePointer(&zeroAddress) {
        SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, UnsafePointer($0))
    }

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

    let isReachable = flags == .Reachable
    let needsConnection = flags == .ConnectionRequired

    return isReachable && !needsConnection

     }
}

3) You can check internet connection anywhere in your project using this code:

 if Reachability.isConnectedToNetwork() == true {
println("Internet connection OK")
} else {
println("Internet connection FAILED")
}

4)If the user is not connected to the internet, you may want to show them an alert dialog to notify them.

if Reachability.isConnectedToNetwork() == true {
println("Internet connection OK")
} else {
println("Internet connection FAILED")
var alert = UIAlertView(title: "No Internet Connection", message: "Make sure your 
 device is connected to the internet.", delegate: nil, cancelButtonTitle: "OK")
alert.show()
}