NSString encoding returns nil on url content

Question

I'm following an iOS Swift guide on Udemy and this is the first issue I cannot work around:

I am supposed to see html etc printed to the console but instead I get null.

This is the section:

    let url = NSURL(string: "https://google.com")
    let task = NSURLSession.sharedSession().dataTaskWithURL(url!) {
        (data, response, error) in
        if error == nil {
            var urlContent = NSString(data: data!, encoding: NSUTF8StringEncoding)
            print(urlContent)
        }
    } 
    task.resume()

If I print just the data then it gives me some content back but when its encoded its nil.

Any help? Cannot move onto the next part until this is resolved.

If `data` isn't `nil` but `urlContent` is, then this means that the data doesn't represent a UTF-8 encoded string. It may be in another encoding or it isn't string data. — rmaddy, Jan 08 '16 at 23:25
This might be useful: http://stackoverflow.com/a/32051684/1187415, it is a method to *detect* the encoding from the HTTP response header. If that does not work, try NSWindowsCP1252StringEncoding or NSISOLatin1StringEncoding. — Martin R, Jan 08 '16 at 23:54

Leo Dabus · Accepted Answer · 2017-05-14T14:58:56.750

The problem there as already mentioned by rmaddy it is the encoding you are using. You need to use NSASCIIStringEncoding.

if let url = URL(string: "https://www.google.com") {
    URLSession.shared.dataTask(with: url) {
        data, response, error in
        guard
            let httpURLResponse = response as? HTTPURLResponse, httpURLResponse.statusCode == 200,
            let data = data, error == nil,
            let urlContent = String(data: data, encoding: .ascii)
        else { return }
        print(urlContent)
    }.resume()
}

Or taking a clue from Martin R you can detect the string encoding from the response:

extension String {
    var textEncodingToStringEncoding: Encoding {
        return Encoding(rawValue: CFStringConvertEncodingToNSStringEncoding(CFStringConvertIANACharSetNameToEncoding(self as CFString)))
    }
}

if let url = URL(string: "https://www.google.com") {
    URLSession.shared.dataTask(with: url) {
        data, response, error in
        guard
            let httpURLResponse = response as? HTTPURLResponse, httpURLResponse.statusCode == 200,
            let data = data, error == nil,
            let textEncoding = response?.textEncodingName,
            let urlContent = String(data: data, encoding: textEncoding.textEncodingToStringEncoding)
            else { return }
        print(urlContent)
    }.resume()
}

NSString encoding returns nil on url content

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