Json 响应数据为零

我收到了响应数据

nil

func fetchSinglePageData() {
    var response: NSData?
    var errors: NSError?
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), {

        response = NSData(contentsOfFile:"url...?project_id=(self.projectID)&project_page=Request", options: NSDataReadingOptions(0), error: &errors)

        print("LatestURL Single page:(response)")

        if response == nil {
            var alertview = UIAlertView(title: "Network Error", message: "Data not received due to network connection.Try again...", delegate: self, cancelButtonTitle: "Ok")
            alertview.show()
        }
        else{
            let jsonDict: NSDictionary = NSJSONSerialization.JSONObjectWithData(response!, options: nil, error: &errors) as NSDictionary
            print("JSON Response Single page:(jsonDict)")
            var statuses = [NSObject : AnyObject]()
            self.lblstartTime?.text = jsonDict["start_time"] as? String
            self.lblcurrentStage?.text = jsonDict["current_stage"] as? String
            self.lblcompletionTime?.text = jsonDict["completion_time"] as? String
            self.lblManager?.text = jsonDict["manager"] as? String
        }
    })
}    

---

project\u id

是从上一页接收的字符串，该字符串工作正常。

快速查看后，可能\缺少：

NSData(contentsOfFile:"url...?project_id=\(self.projectID)&project_page=Request"

在这方面：

response   = NSData(contentsOfFile:"url...?project_id=(self.projectID)&project_page=Request", options: NSDataReadingOptions(0), error: &errors)

您有

project\u id=（self.projectID）

，要使用插值，您应该有

project\u id=\（self.projectID）

我建议您分离代码以生成完整的URL，然后将URL打印到控制台，并确保它是您所期望的

然后，您可以自己访问url并检查服务器返回的内容，然后，一旦知道您有正确的url和响应，就可以对响应进行反序列化

编辑：使用URLSession更新（Swift 3版本）

---

在swift 3中

 //make a url request

 let urlString = "your_url"
 let urlRequest = URLRequest.init(url: URL.init(string: urlString)!, cachePolicy: .reloadIgnoringCacheData, timeoutInterval: 50)

  //create a session
  let session = URLSession.shared

  let task = session.dataTask(with: request) { (data, urlResponse, error) in
        if error != nil{
            //handle error
            return
        }else{
            if let responseData = data{
             let  jsonDict  = try JSONSerialization.jsonObject(with: responseData, options: [])as? [String:Any]
             //handle your response here

            }
        }
    }
  task.resume()

在swift 2.2中

    let urlString = "your_url"

    let request = NSURLRequest(URL: NSURL(string: urlString)!, cachePolicy: .ReloadIgnoringLocalCacheData, timeoutInterval: 50)

    let session = NSURLSession.sharedSession()

    let task = session.dataTaskWithRequest(request) { (data, response, error) in

        if error != nil{
            //handel error
            print(error!.localizedDescription)
            return
        }

        if let responseData = data{

            do{
                if  let jsonDict = try NSJSONSerialization.JSONObjectWithData(responseData, options: [])as? [String:Any]{

                    //you have data in json dict

                }

            }catch{
                print("error in parsing response")
                return
            }


        }
    }
    task.resume()

---

根据Jitendra Solanki的回答，这是我的回答。我已经对代码进行了更改，现在正在Swift 1.2中运行。使用URLSession从服务器获取数据。该url包含self.projectID，而不是实际的项目ID。您需要使用

\（self.projectID）

要将值传递到字符串中，那么输入projectID的新URL是什么？你有错误吗？您最好使用NSURLSessionI，因为您可以看到您使用的是旧版本的xcode和swift。我已经提供了一个例子，说明你如何做到这一点，但它在Swift 3中。我使用xcode 8。如果你计划将此应用程序推送到商店，你需要更新，我相信苹果已经停止支持iOS9及以下版本了。你为什么删除了接受的答案？这没有帮助吗？@DilipTiwari，我编辑了答案以便在swift 2.2中工作，所有版本的方法都是相同的，只是api方法的名称在swift 3中更改了。我认为在swift 1.2中不应该有太多的更改，您可以使用swift 2.2的代码。让我们来看看。

    let urlString = "your_url"

    let request = NSURLRequest(URL: NSURL(string: urlString)!, cachePolicy: .ReloadIgnoringLocalCacheData, timeoutInterval: 50)

    let session = NSURLSession.sharedSession()

    let task = session.dataTaskWithRequest(request) { (data, response, error) in

        if error != nil{
            //handel error
            print(error!.localizedDescription)
            return
        }

        if let responseData = data{

            do{
                if  let jsonDict = try NSJSONSerialization.JSONObjectWithData(responseData, options: [])as? [String:Any]{

                    //you have data in json dict

                }

            }catch{
                print("error in parsing response")
                return
            }


        }
    }
    task.resume()

func singlePageData(){

    var errors: NSError?

    let urlString = "xyz.com"
    print("URL RESPONSE  \(urlString)")

    let request = NSURLRequest(URL: NSURL(string: urlString), cachePolicy: .ReloadIgnoringLocalCacheData, timeoutInterval: 50)

    let session = NSURLSession.sharedSession()

    let task = session.dataTaskWithRequest(request) { (data, response, error) in

        if error != nil{
            //handel error
            print(error!.localizedDescription)
            var alertview = UIAlertView(title: "Network Error", message: "Data not received due to network connection.Try again...", delegate: self, cancelButtonTitle: "Ok")
            alertview.show()
            return
        }

        if let responseData = data{

              var jsonDict: NSDictionary = NSJSONSerialization.JSONObjectWithData(responseData, options: NSJSONReadingOptions.MutableContainers, error: &errors) as NSDictionary!

            dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), {

            println("Json dict value  \(jsonDict)")
            self.lblprojectName?.text = jsonDict["name"] as? String
            println("lblprojectName:  \(self.lblprojectName?.text)")
            self.lblstartTime?.text = jsonDict["start_time"] as? String
             println("lblstartTime :  \(self.lblstartTime?.text)")
            self.lblcurrentStage?.text = jsonDict["current_stage"] as? String
             println("lblcurrentStage :  \(self.lblcurrentStage?.text)")
            self.lblcompletionTime?.text = jsonDict["completion_time"] as? String
             println("lblcompletionTime :  \(self.lblcompletionTime?.text)")
            self.lblManager?.text = jsonDict["manager"] as? String

            })

            }
        }
    task.resume()

}