我正在关注有关Udemy的iOS Swift指南,这是我无法解决的第一个问题:
我应该看到html等打印到控制台,但是我得到了null。
这是本节:
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()
如果我只打印数据,那么它给了我一些内容,但是当它编码为零时。
有什么帮助吗?在解决此问题之前,无法移动到下一部分。
rmaddy已经提到的问题是您使用的编码。您需要使用NSASCIIStringEncoding。
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() }
或从Martin R中获取线索,您可以从响应中检测字符串编码:
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() }