有人可以找到錯誤，並驗證我的Swift NSURLSession代碼？

Question

我正在使用Swift編寫我的第一個基本IOS應用程序，它將輪詢Proliphix IP恆溫器並顯示溫度。我已經使用Paw將HTTP Post轉換爲NSURLSession，但轉換後的代碼在Xcode Playground中加載時似乎有3個語法錯誤。

我現在的目標是讓它在Playground中運行，但最終會在我的應用程序代碼中使用它。是否有人可以在您自己的Xcode Playground中加載此代碼並修復錯誤並使其正常工作？該URL是恆溫器的公共IP地址，如果工作正常，它將輪詢恆溫器並返回OID4.3.2.3的值，並且= 772 &（當前爲77.2度）。

class MyRequestController { 
    func sendRequest() { 
     /* Configure session, choose between: 
      * defaultSessionConfiguration 
      * ephemeralSessionConfiguration 
      * backgroundSessionConfigurationWithIdentifier: 
     And set session-wide properties, such as: HTTPAdditionalHeaders, 
     HTTPCookieAcceptPolicy, requestCachePolicy or timeoutIntervalForRequest. 
     */ 
     let sessionConfig = NSURLSessionConfiguration.defaultSessionConfiguration() 

     /* Create session, and optionally set a NSURLSessionDelegate. */ 
     let session = NSURLSession(configuration: sessionConfig, delegate: nil, delegateQueue: nil) 

     /* Create the Request: 
      My API (POST http://my-thermostat.dyndns.org:8083/get) 
     */ 

     var URL = NSURL(string: "http://my-thermostat.dyndns.org:8083/get") 
     let request = NSMutableURLRequest(URL: URL!) 
     request.HTTPMethod = "POST" 

     // Headers 

     request.addValue("Basic dXNlcjpwYXNzd29yZA==", forHTTPHeaderField: "Authorization") 

     // Form URL-Encoded Body 

     let bodyParameters = [ 
      "OID4.3.2.3": "", 
     ] 
     let bodyString = self.stringFromQueryParameters(bodyParameters) 
     request.HTTPBody = bodyString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true) 

     /* Start a new Task */ 
     let task = session.dataTaskWithRequest(request, completionHandler: { (data : NSData!, response : NSURLResponse!, error : NSError!) -> Void in 
      if (error == nil) { 
       // Success 
       let statusCode = (response as NSHTTPURLResponse).statusCode 
       println("URL Session Task Succeeded: HTTP \(statusCode)") 
      } 
      else { 
       // Failure 
       println("URL Session Task Failed: %@", error.localizedDescription); 
      } 
     }) 
     task.resume() 
    } 

    /** 
    This creates a new query parameters string from the given NSDictionary. For 
    example, if the input is @{@"day":@"Tuesday", @"month":@"January"}, the output 
    string will be @"day=Tuesday&month=January". 
    @param queryParameters The input dictionary. 
    @return The created parameters string. 
    */ 
    func stringFromQueryParameters(queryParameters : Dictionary<String, String>) -> String { 
     var parts: [String] = [] 
     for (name, value) in queryParameters { 
      var part = NSString(format: "%@=%@", 
       name.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!, 
       value.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!) 
      parts.append(part) 
     } 
     return "&".join(parts) 
    } 

    /** 
    Creates a new URL by adding the given query parameters. 
    @param URL The input URL. 
    @param queryParameters The query parameter dictionary to add. 
    @return A new NSURL. 
    */ 
    func NSURLByAppendingQueryParameters(URL : NSURL!, queryParameters : Dictionary<String, String>) -> NSURL { 
     let URLString : NSString = NSString(format: "%@?%@", URL.absoluteString!, self.stringFromQueryParameters(queryParameters)) 
     return NSURL(string: URLString)! 
    } 
} 

我認爲我需要以上代碼在Playground上面的以下工作正常嗎？

import Foundation 
import XCPlayground 

最後，我用來轉換的HTTP Post來自以下，Paw將它轉換爲上面的NSURLSession。

POST /get HTTP/1.1 
Authorization: Basic dXNlcjpwYXNzd29yZA== 
Content-Type: application/x-www-form-urlencoded 
Host: my-thermostat.dyndns.org:8083 
Connection: close 
User-Agent: Paw/2.2.2 (Macintosh; OS X/10.10.4) GCDHTTPRequest 
Content-Length: 11 

OID4.3.2.3= 

謝謝你的幫忙！

Answer 1

如果我用你的代碼創建一個遊樂場，我會得到三個錯誤。

一個在功能sendRequest()，你必須改變這一行：

let statusCode = (response as NSHTTPURLResponse).statusCode

到

let statusCode = (response as! NSHTTPURLResponse).statusCode

（as!而不是as）

一個在功能stringFromQueryParameters，你必須將下面一行

parts.append(part)

改變

parts.append(part as String)

（添加as String）

，一個在功能NSURLByAppendingQueryParameters，你必須改變這一點：

return NSURL(string: URLString)!

這樣：

return NSURL(string: URLString as String)!

（添加as String）

然後編譯器似乎滿足了......至少在我的機器上:-)

是的，你需要按照您的想法導入Foundation和XCPlayground。

此外，如果您需要進行異步調用...比如這裏的情況下，你需要在你的代碼的頂部這種方法：

XCPSetExecutionShouldContinueIndefinitely()

（你可以閱讀更多關於它here）

最後，真正看到你的代碼運行，你可以添加到您的代碼的底部，類定義後：

let requestController = MyRequestController() 
requestController.sendRequest() 

下面是完整的代碼

import Foundation 
import XCPlayground 

XCPSetExecutionShouldContinueIndefinitely() 

class MyRequestController { 
    func sendRequest() { 
     /* Configure session, choose between: 
     * defaultSessionConfiguration 
     * ephemeralSessionConfiguration 
     * backgroundSessionConfigurationWithIdentifier: 
     And set session-wide properties, such as: HTTPAdditionalHeaders, 
     HTTPCookieAcceptPolicy, requestCachePolicy or timeoutIntervalForRequest. 
     */ 
     let sessionConfig = NSURLSessionConfiguration.defaultSessionConfiguration() 

     /* Create session, and optionally set a NSURLSessionDelegate. */ 
     let session = NSURLSession(configuration: sessionConfig, delegate: nil, delegateQueue: nil) 

     /* Create the Request: 
     My API (POST http://my-thermostat.dyndns.org:8083/get) 
     */ 

     var URL = NSURL(string: "http://my-thermostat.dyndns.org:8083/get") 
     let request = NSMutableURLRequest(URL: URL!) 
     request.HTTPMethod = "POST" 

     // Headers 

     request.addValue("Basic dXNlcjpwYXNzd29yZA==", forHTTPHeaderField: "Authorization") 

     // Form URL-Encoded Body 

     let bodyParameters = [ 
      "OID4.3.2.3": "", 
     ] 
     let bodyString = self.stringFromQueryParameters(bodyParameters) 
     request.HTTPBody = bodyString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true) 

     /* Start a new Task */ 
     let task = session.dataTaskWithRequest(request, completionHandler: { (data : NSData!, response : NSURLResponse!, error : NSError!) -> Void in 
      if (error == nil) { 
       // Success 
       let statusCode = (response as! NSHTTPURLResponse).statusCode 
       println("URL Session Task Succeeded: HTTP \(statusCode)") 
      } 
      else { 
       // Failure 
       println("URL Session Task Failed: %@", error.localizedDescription); 
      } 
     }) 
     task.resume() 
    } 

    /** 
    This creates a new query parameters string from the given NSDictionary. For 
    example, if the input is @{@"day":@"Tuesday", @"month":@"January"}, the output 
    string will be @"day=Tuesday&month=January". 
    @param queryParameters The input dictionary. 
    @return The created parameters string. 
    */ 
    func stringFromQueryParameters(queryParameters : Dictionary<String, String>) -> String { 
     var parts: [String] = [] 
     for (name, value) in queryParameters { 
      var part = NSString(format: "%@=%@", 
       name.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!, 
      value.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!) 
      parts.append(part as String) 
     } 
     return "&".join(parts) 
    } 

    /** 
    Creates a new URL by adding the given query parameters. 
    @param URL The input URL. 
    @param queryParameters The query parameter dictionary to add. 
    @return A new NSURL. 
    */ 
    func NSURLByAppendingQueryParameters(URL : NSURL!, queryParameters : Dictionary<String, String>) -> NSURL { 
     let URLString : NSString = NSString(format: "%@?%@", URL.absoluteString!, self.stringFromQueryParameters(queryParameters)) 
     return NSURL(string: URLString as String)! 
    } 
} 

let requestController = MyRequestController() 
requestController.sendRequest() 

希望這會有所幫助