iOS Swift 3 POST问题

Question

我有一些代码，我用了一段时间后，完美的工作。现在，我想在我的新项目，这是SWIFT 3使用它，虽然我有固定的大多数错误，我仍然有两人离开如下：

下面的代码行：var _: NSData? = NSURLConnection.sendSynchronousRequest(request as URLRequest, returning:&response) as NSData产生以下错误：Call can throw, but it is not marked with 'try' and the error is not handled

以下代码行：NSLog("Response code: %ld", res?.statusCode ?? <#default value#>);产生以下错误：Editor placeholder in source file。

任何帮助表示赞赏。

下面是完整的代码，可以帮助解决这个问题：

 func webViewDidFinishLoad(_ webView: UIWebView) { 
     UIApplication.shared.isNetworkActivityIndicatorVisible = false 

     let post:NSString = "userid=349&devicetoken=walan" 

     NSLog("PostData: %@",post); 

     let url:NSURL = NSURL(string: "https://str8red.com/updateAPN")! 

     let postData:NSData = post.data(using: String.Encoding.ascii.rawValue)! as NSData 

     let postLength:NSString = String(postData.length) as NSString 

     let request:NSMutableURLRequest = NSMutableURLRequest(url: url as URL) 
     request.httpMethod = "POST" 
     request.httpBody = postData as Data 
     request.setValue(postLength as String, forHTTPHeaderField: "Content-Length") 
     request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type") 
     request.setValue("application/json", forHTTPHeaderField: "Accept") 


     var _: NSError? 
     var response: URLResponse? 

     var _: NSData? = NSURLConnection.sendSynchronousRequest(request as URLRequest, returning:&response) as NSData 


     let res = response as! HTTPURLResponse!; 

     NSLog("Response code: %ld", res?.statusCode ?? <#default value#>); 

} 

Answer 1

您可以添加关键字try和环绕声和do {}赶上{}声明如下：

do { 

try NSURLConnection.sendSynchronousRequest(request as URLRequest, returning:&response) as NSData 
} catch { 
    print(error) 
} 

你将仍然有一个警告，该功能已被弃用，因为iOS 9。

我会看看尝试看看整个功能如何可以重写在iOS 10，Swift 3.1语法，但有一个da说它可能会破坏，并且与其他遗留代码看起来会非常不同。敬请期待，我会再次更新这个答案。

至于“占位符错误”你可以把像“500”的一些值，例如默认为“内部服务器错误”

NSLog("Response code: %ld", res?.statusCode ?? 500); 

更新：这里是更新到斯威夫特3的功能， iOS 10.

我只根据函数的原意进行更新。只需语法/ API更新，不删除/添加任何功能。

func webViewDidFinishLoad(_ webView: UIWebView) { 
    UIApplication.shared.isNetworkActivityIndicatorVisible = false 

    let post:String = "userid=349&devicetoken=walan" 

    NSLog("PostData: %@",post); 

    let url:URL = URL(string: "https://str8red.com/updateAPN")! 

    let postData:Data = post.data(using: String.Encoding(rawValue: String.Encoding.ascii.rawValue))! 

    let postLength: String = String(postData.count) 

    var request:URLRequest = URLRequest(url: url as URL) 

    request.httpMethod = "POST" 
    request.httpBody = postData as Data 
    request.setValue(postLength, forHTTPHeaderField: "Content-Length") 
    request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type") 
    request.setValue("application/json", forHTTPHeaderField: "Accept") 

    var _: NSError? 
    var response: URLResponse? 

    URLSession.shared.dataTask(with: request) { (data, res, error) in 

     guard error == nil else { 
      print(error!) 
      return 
     } 

     response = res 
    } 

    let res = response as! HTTPURLResponse!; 

    NSLog("Response code: %ld", res?.statusCode ?? 500); 
}