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  1. Is it possible to cancel an NSURLConnection started with sendAsynchronousRequest:queue:completionHandler:?

  2. Why doesn't sendAsynchronousRequest:queue:completionHandler: return the NSURLConnection object it creates so that I can cancel it?

ma11hew28
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1 Answers1

5

EDIT - Since my provided answer seems to have been wrong, you should check out the following related question and its answers:

How can I cancel an asynchronous call through NSURLConnection sendAsynchronousRequest?

Old answer:

In your header of your class (e.g. ViewController), declare an operation queue:

NSOperationQueue *downloadOperationQueue;

To download a file call something like the following:

downloadOperationQueue = [[NSOperationQueue alloc] init];
NSURLRequest *fileRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.google.com/images/nav_logo114.png"]
                                             cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData
                                         timeoutInterval:10];
[NSURLConnection sendAsynchronousRequest:fileRequest
                                   queue:downloadOperationQueue
                       completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
                           NSLog(@"download successful");
                       }];

To cancel the download later on call:

[downloadOperationQueue cancelAllOperations];
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gchbib
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    According to the [doc](http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSURLConnection_Class/Reference/Reference.html): "...queue: The operation queue to which the handler block is dispatched when the request completes or failed". ie: the queue paramater is the queue that handles the completion block, not the queue that takes care of the request itself – Thomas Feb 05 '13 at 21:21
  • WTF? it will not cancel the request :D – l0gg3r Sep 22 '14 at 07:27
  • Yes. That's why I edited the answer and provided a link to another answer. – gchbib Sep 24 '14 at 10:53
  • Yes, the old answer just set isCancelled to Yes and you need to manually check and behave accordingly :/ – Skodik.o Aug 09 '16 at 12:18