How to check if Link is broken with WKWebview? - ios

Question

I use WKWebview to load a URL.
let webView = WKWebview()
let request: NSMutableURLRequest = NSMutableURLRequest(URL: url!)
webView.loadRequest(request)
How can I detect if the link the webView should load is broken?

Answer 1

You can use canOpenUrl method:
UIApplication.sharedApplication().canOpenURL(url)
It will do the url validation and if the link is ok it returns true.
It's mostly use before you call:
UIApplication.sharedApplication().openURL(url)
to make sure this link can be open in safari but it should help you here too.
Make sure the link starts with http:// or https://.
Edited:
It will just check is the link is a correct url.
If you want to see the page is offline, authorisation issues, etc. you can implement WKNavigationDelegate protocol and check out this method:
- webView:didFailNavigation:withError:
this should give you more info.
It's always good idea to use: str.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAl‌​lowedCharacterSet())!
it make sure that you don't pass a character which are not allowed in URL.
Edited 2:
To detect the status code you can try to implement:
- webView:decidePolicyForNavigationResponse:decisionHandler:
the navigation response is an NSURLResponse instance but
whenever you make an HTTP request, the NSURLResponse object you get back is actually an instance of the NSHTTPURLResponse class so you should cast it to NSHTTPURLResponse. That should give you a statusCode.
In the last line in the method you should call handler, for example decisionHandler(WKNavigationResponsePolicyAllow).

Answer 2

Ref: Answer exists here
if let url = NSURL(string: yourUrlString) {
var canOpen = UIApplication.sharedApplication().canOpenURL(url)
}

Answer 3

If you want to check if url string is correct and valid - just create NSURL object, if path contains error it will cast to nil:
let string = "http://google.com"
let url = NSURL(string: string)
let brokenString = "http:\\brokenurl.12"
let brokenUrl = NSURL(string: brokenString) // nil - it's not valid!

Answer 4

If you have implemented NSURLConnectionDelegate then below solution can be used.
didFailWithError method of NSURLConnectionDelegate can be used for this.
This method get called if an error occurs during the loading of a resource.
Can refer to below link
https://developer.apple.com/documentation/foundation/nsurlconnectiondelegate/1418443-connection