swift网络请求的相关方法

import UIKit

class DownLocader: NSObject,NSURLSessionDownloadDelegate {

    

    var session: NSURLSession?

    

    override init() {

        

        super.init()

        

        let imageURL = NSURL(string: "https://httpbin.org/image/png")!

        

        session = NSURLSession(configuration: NSURLSessionConfiguration.backgroundSessionConfigurationWithIdentifier("taask"), delegate: self, delegateQueue: nil)

        

        session?.downloadTaskWithURL(imageURL).resume()

    }

    

    

    func URLSession(session: NSURLSession, downloadTask: NSURLSessionDownloadTask, didFinishDownloadingToURL location: NSURL){

    

         print("下载完成")

    

    }

    

    func URLSession(session: NSURLSession, downloadTask: NSURLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64)

    

    {

       print("正在下载 \(totalBytesWritten)/\(totalBytesExpectedToWrite)")

    

    }

    

    func URLSession(session: NSURLSession, downloadTask: NSURLSessionDownloadTask, didResumeAtOffset fileOffset: Int64, expectedTotalBytes: Int64)

    

    {

        print("从 \(fileOffset)处恢复下载，一共 \(expectedTotalBytes)")

    

    }

    

    

}

class ViewController: UIViewController {

    @IBOutlet weak var imageView: UIImageView!

    

    override func viewDidLoad() {

        

        super.viewDidLoad()

        // Do any additional setup after loading the view, typically from a nib.

        

           //网络请求

        

        

        var dow: DownLocader

        dow = DownLocader()

        

    

        

        if let url = NSURL(string: "https://httpbin.org/get"){

            

            NSURLSession.sharedSession().dataTaskWithURL(url

            , completionHandler: { (let data, let Response, let error) -> Void in

    

    print(Response)

    

            }).resume()

        

        }

        

        

        let imageURL = NSURL(string: "https://httpbin.org/image/png")!

        

//        NSURLSession.sharedSession().downloadTaskWithURL(imageURL) {Loca, response, error) -> Void in

//           

//            

//            guard let url = Loca else { return }

//            guard let imageData = NSData(contentsOfURL: url) else { return }

//            guard let image = UIImage(data: imageData) else { return }

//

//        }.resume()

        

        NSURLSession.sharedSession().downloadTaskWithURL(imageURL) { (Loca, response, error) -> Void in

            

            guard let url = Loca else { return }

            guard let imageData = NSData(contentsOfURL: url) else { return }

            guard let image = UIImage(data: imageData) else { return }

            

            dispatch_async(dispatch_get_main_queue(), { () -> Void in

                

                

                self.imageView.image=image;

            })

            

            

            

        }.resume()

        

        

        

        

        

        let uploadURL = NSURL(string: "https://httpbin.org/image/png")!

        let request = NSURLRequest(URL: uploadURL)

        

        let fileURL = NSURL(fileURLWithPath: "pathToUpload")

        NSURLSession.sharedSession().uploadTaskWithRequest(request, fromFile: fileURL) { (let data, let Response, let error) -> Void in

            

            print("上传成功响应\(Response)")

        

        }.resume()

    }

    

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

        // Dispose of any resources that can be recreated.

    }

}