Check whether internet connection is available

Question

I am writing a function that checks whether a users device is connected to the internet. If it is not it warns the users with an Alert box.

Initially I was using the following below which worked perfectly:

var data = try NSURLConnection.sendSynchronousRequest(request, returningResponse: &response) as NSData?

But this has been deprecated in iOS 9.

So I changed my code to the following.

import Foundation
import SystemConfiguration

public class Reachability {

class func isConnectedToNetwork()->Bool{

    var Status:Bool = false
    let url = NSURL(string: "https://google.com/")
    var response: NSURLResponse?
    let request = NSMutableURLRequest(URL: url!)
    request.HTTPMethod = "HEAD"
    request.cachePolicy = NSURLRequestCachePolicy.ReloadIgnoringLocalAndRemoteCacheData
    request.timeoutInterval = 10.0

    let sessionConfig = NSURLSessionConfiguration.defaultSessionConfiguration()
    let session = NSURLSession(configuration: sessionConfig, delegate: nil, delegateQueue: nil)

    let task = session.dataTaskWithRequest(request, completionHandler: {data, response, err -> Void in

        if let httpResponse = response as? NSHTTPURLResponse {
            if httpResponse.statusCode == 200 {
                Status = true
            }
        } 
    })

    task.resume()
    return Status
}}

The issue is that it always says that there is NO Internet connection which is obviously wrong. Which means the "Bool" is always false. What am I doing wrong?

Thanks in advance.

Please see the following answer. http://stackoverflow.com/a/30743763/1180206 — Imran, Sep 28 '15 at 07:55
@Paulw11 Thank you for reply. Any suggestions on how to fix this? — Skywalker, Sep 28 '15 at 07:58

score 3 · Accepted Answer · answered Sep 28 '15 at 07:58

Using reachability or some other test is how you should meet your actual requirement.

However, to answer your question, the reason that this always returns false is that the data task is asynchronous - that is it will complete independently of the function call, so by the time it completes and tries to set status to true, the function has already returned false

score 2 · Answer 2 · answered Sep 28 '15 at 07:51

2

The recommended way is to send the request that you actually want to send, and determine whether it succeeds or fails, and if it fails, determine why it fails. There is no way to detect reliably whether there is a connection or not.

answered Sep 28 '15 at 07:51

gnasher729

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Check whether internet connection is available

2 Answers2