Detect if internet connection is available (WIFI and 4G) on SWIFT 3

Question

Can anyone help me to find a way to detect if an Internet connection is available using Swift 3?

I'm using the following code:

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(MemoryLayout.size(ofValue: zeroAddress))
        zeroAddress.sin_family = sa_family_t(AF_INET)

        let defaultRouteReachability = withUnsafePointer(to: &zeroAddress) {
            SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, UnsafePointer)
        }

        var flags: SCNetworkReachabilityFlags = SCNetworkReachabilityFlags(rawValue: 0)
        if SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) == false {
            return false
        }
        let isReachable = flags == .reachable
        let needsConnection = flags == .connectionRequired

        return isReachable && !needsConnection
    }
}

but I have an error message:

Error Message

Welcome to StackOverflow! Before asking a new question, please search (here or on Google) to find out if anyone already asked the same one before. — Guillaume Algis, Oct 12 '16 at 15:58
http://stackoverflow.com/a/25623647/1187415 was updated for Swift 3 some time ago. — Martin R, Oct 12 '16 at 16:44

David Seek · Accepted Answer · 2016-10-12T17:04:07.103

4

I'm using a slightly different Reachability function. Try mine. It should work for you. I'm using it in almost every of my apps and I'm not having any kind of problems with it.

Written in Swift3

import Foundation
import SystemConfiguration

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)

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

}

Called by:

if Reachability.isConnectedToNetwork() == true {
    xy
} else {
    yz
}

edited Oct 12 '16 at 17:04

answered Oct 12 '16 at 16:24

David Seek

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thanks for letting me know @rmaddy , I'll edit may answer – David Seek Oct 12 '16 at 16:30
Thanks David for your help. It worked for me; I used your code. – Patrick Oct 12 '16 at 16:33
Okay. Glad to help. I've upvoted your question. Hope other users will follow my example, so you're getting in a positive value. – David Seek Oct 12 '16 at 16:34
Thanks again David. – Patrick Oct 12 '16 at 16:38
Note that the forced unwrapping `defaultRouteReachability!` would crash if SCNetworkReachabilityCreateWithAddress() returns nil (however I don't know under what condition that would happen). Compare http://stackoverflow.com/a/25623647/1187415. – Martin R Oct 12 '16 at 16:58
@MartinR thanks for the hint. i've edited and handled it with a guard block now – David Seek Oct 12 '16 at 17:04

Detect if internet connection is available (WIFI and 4G) on SWIFT 3

1 Answers1