nsurlconnection - 取消 NSURLConnection 以 sendAsynchronousRequest :queue:completionHandler:? 开始

Question

是否可以取消 NSURLConnection开始于 sendAsynchronousRequest:queue:completionHandler: ?

为什么不sendAsynchronousRequest:queue:completionHandler:返回 NSURLConnection它创建的对象以便我可以取消它？

Answer 1

编辑 - 由于我提供的答案似乎有误，您应该查看以下相关问题及其答案:

How can I cancel an asynchronous call through NSURLConnection sendAsynchronousRequest?

旧答案:

在类的标题(例如 ViewController)中，声明一个操作队列:

NSOperationQueue *downloadOperationQueue;

要下载文件，请调用如下所示的内容:

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");
                       }];

稍后在通话中取消下载:

[downloadOperationQueue cancelAllOperations];