sendAsynchronousRequest was deprecated in iOS 9, How to alter code to fix

Below is my code I am getting the issue with:

func parseFeedForRequest(request: NSURLRequest, callback: (feed: RSSFeed?, error: NSError?) -> Void)
{
    NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()) { (response, data, error) -> Void in

        if ((error) != nil)
        {
            callback(feed: nil, error: error)
        }
        else
        {
            self.callbackClosure = callback
            
            let parser : NSXMLParser = NSXMLParser(data: data!)
            parser.delegate = self
            parser.shouldResolveExternalEntities = false
            parser.parse()
        }
    }
}

This is now deprecated as of iOS 9, and is telling me to use dataTaskWithRequest instead. Can someone help me change sendAsync with dataTask, I don't know how to.

Use NSURLSession instead like below,

For Objective-C

NSURLSession *session = [NSURLSession sharedSession];
[[session dataTaskWithURL:[NSURL URLWithString:"YOUR URL"]
          completionHandler:^(NSData *data,
                              NSURLResponse *response,
                              NSError *error) {
            // handle response
 
  }] resume];

For Swift,

    var request = NSMutableURLRequest(URL: NSURL(string: "YOUR URL")!)
    var session = NSURLSession.sharedSession()
    request.HTTPMethod = "POST"
    
    var params = ["username":"username", "password":"password"] as Dictionary<String, String>
    
    request.HTTPBody = try? NSJSONSerialization.dataWithJSONObject(params, options: [])
    
    request.addValue("application/json", forHTTPHeaderField: "Content-Type")
    request.addValue("application/json", forHTTPHeaderField: "Accept")
    
    var task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
        print("Response: \(response)")})
    
    task.resume()

For asynchronously query, from Apple docs

> Like most networking APIs, the NSURLSession API is highly > asynchronous. It returns data in one of two ways, depending on the > methods you call: > > To a completion handler block that returns data to your app when a > transfer finishes successfully or with an error. > > By calling methods on your custom delegate as the data is received. > > By calling methods on your custom delegate when download to a file is > complete.

Swift implementation

let session = NSURLSession.sharedSession()
session.dataTaskWithRequest(request) { (data, response, error) -> Void in
            
}

Swift 3.0

var request = URLRequest(url: URL(string: "http://example.com")!)
request.httpMethod = "POST"
let session = URLSession.shared
    
session.dataTask(with: request) {data, response, err in
    print("Entered the completionHandler")
}.resume()

This is the swift 2.1 version:

let request = NSMutableURLRequest(URL: NSURL(string: "YOUR URL")!)
let session = NSURLSession.sharedSession()
request.HTTPMethod = "POST"
    
let params = ["username":"username", "password":"password"] as Dictionary<String, String>
    
request.HTTPBody = try! NSJSONSerialization.dataWithJSONObject(params, options: [])
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
    
let task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
print("Response: \(response)")})
    
task.resume()

Swift 2.0:

Old (replace with New below):

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue()) { (response, data, error) -> Void in

// Code

}

New:

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

// Code

}
task.resume()

Swift 4

let params = ["email":"[email protected]", "password":"123456"] as Dictionary<String, String>

var request = URLRequest(url: URL(string: "http://localhost:8080/api/1/login")!)
request.httpMethod = "POST"
request.httpBody = try? JSONSerialization.data(withJSONObject: params, options: [])
request.addValue("application/json", forHTTPHeaderField: "Content-Type")

let session = URLSession.shared
let task = session.dataTask(with: request, completionHandler: { data, response, error -> Void in

    do {
        let json = try JSONSerialization.jsonObject(with: data!) as! Dictionary<String, AnyObject>
        print(json)
    } catch {
        print("error")
    }

})

task.resume()

with swift 3.1

let request = NSMutableURLRequest(url: NSURL(string: image_url_string)! as URL)
    let session = URLSession.shared
    request.httpMethod = "POST"
    
    let params = ["username":"username", "password":"password"] as Dictionary<String, String>
    
    request.httpBody = try? JSONSerialization.data(withJSONObject: params, options: [])
    
    request.addValue("application/json", forHTTPHeaderField: "Content-Type")
    request.addValue("application/json", forHTTPHeaderField: "Accept")
    
    let task = session.dataTask(with: request as URLRequest, completionHandler: {data, response, error -> Void in
        print("Response: \(String(describing: response))")})
    
    task.resume()

Illustrating with an example, the alternative code to the deprecation of:

>sendAsynchronousRequest(_:queue:completionHandler:)' was deprecated in iOS 9.0: Use [NSURLSession dataTaskWithRequest:completionHandler:]

Tested and works in Swift 2.1 onwards.

import UIKit

class ViewController: UIViewController {
    
    
    @IBOutlet var theImage: UIImageView!
 

    override func viewDidLoad() {
        super.viewDidLoad()

        
        let url = NSURL(string: "https://upload.wikimedia.org/wikipedia/commons/6/6a/Johann_Sebastian_Bach.jpg")


        let task = NSURLSession.sharedSession().dataTaskWithURL(url!) { (data, response, error) -> Void in
            
            if error != nil {
                print("thers an error in the log")
            } else {
                
                dispatch_async(dispatch_get_main_queue()) {
                let image = UIImage(data: data!)
                self.theImage.image = image
                
                }
            }

        }
        
        task.resume()
    
    }

}

//Displays an image on the ViewControllers ImageView. Connect an outlet of the ImageView

Here is the SWIFT3.0 Version of Nilesh Patel's Answer with JSONSerialised data

let url = URL(string: "<HERE GOES SERVER API>")!
            var request = URLRequest(url: url)
            request.httpMethod = "POST" //GET OR DELETE etc....
            request.setValue("application/json", forHTTPHeaderField: "Content-Type")
            request.setValue("<ValueforAuthorization>", forHTTPHeaderField: "Authorization")
            let parameter = [String:Any]() //This is your parameters [String:Any]
            do {
                let jsonData = try JSONSerialization.data(withJSONObject: parameter, options: .prettyPrinted)
                // here "jsonData" is the dictionary encoded in JSON data
                request.httpBody = jsonData
                let session = URLSession(configuration: .default)
                let task = session.dataTask(with: request, completionHandler: { (incomingData, response, error) in
                    if let error = error {
                        print(error.localizedDescription)
                        print(request)
                    }else if let response = response {
                        print(response)
                    }else if let incomingData = incomingData {
                        print(incomingData)
                    }
                })
                task.resume()
                
            } catch {
                print(error.localizedDescription)
            }

Swift 4.2

This worked for me:

func loadImageFromURL(URL: NSURL) {
    let request = URLRequest(url: URL as URL)
    let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
        if let imageData = data {
            DispatchQueue.main.async {
                self.imageView.image = UIImage(data: imageData)
            }
        }
    }
    task.resume()
}

I had to add "DispatchQueue.main.async { }" because I had a runtime warning, since only the main thread is supposed to modify UI elements.