NSURLSession取消任务 [英] NSURLSession cancel Task

问题描述

我使用以下配置创建新的NSURLSession

  if（！self.session）{
 NSURLSessionConfiguration * config = [NSURLSessionConfiguration backgroundSessionConfiguration：[self uniquieIdentifier]]; 
 config.discretionary = NO; 
 self.session = [NSURLSession sessionWithConfiguration：config delegate：self delegateQueue：[NSOperationQueue mainQueue]]; 
} 
  

然后按下按钮我试图停止所有当前的下载任务。

  [[[self session] delegateQueue] setSuspended：YES]; 
 [[self session] invalidateAndCancel];不过我得到的响应委托方法didFinishDownloadingToURL，我很确定没有新的会话或下载任务是在这一点之后创建的。如何停止所有任务的发生？
解决方案
我不建议使用invalidateAndCancel方法导致队列及其标识符保持无效，无法重复使用，直到您重置整个设备。
 
 
 
  NSURLSession类参考 
 
 
 
我使用此代码取消所有待处理的任务。
   - （void）cancelDownloadFiles 
 {
 
 [self.session getTasksWithCompletionHandler： （NSArray * dataTasks，NSArray * uploadTasks，NSArray * downloadTasks）{
 
 for（NSURLSessionTask * _task in downloadTasks）
 {
 [_task cancel]; 
 
 id< FFDownloadFileProtocol> file = [self getFileDownloadInfoIndexWithTaskIdentifier：_task.taskIdentifier]; 
 
 [file.downloadTask cancel]; 
 
 //更改所有相关属性。 
 file.isDownloading = NO; 
 file.taskIdentifier = -1; 
 file.downloadProgress = 0.0; 
 
} 
 
}]; 
 
 cancel = YES; 
} 
  
 
I create new NSURLSession with following configs
 if (!self.session) {
            NSURLSessionConfiguration *config = [NSURLSessionConfiguration backgroundSessionConfiguration:[self uniquieIdentifier]];
            config.discretionary = NO;
            self.session = [NSURLSession sessionWithConfiguration:config delegate:self delegateQueue:[NSOperationQueue mainQueue]];
        }
and on after pressing a button I am trying to stop all current download tasks. 
[[[self session] delegateQueue] setSuspended:YES];
[[self session] invalidateAndCancel];
Nevertheless I get responses in delegate method didFinishDownloadingToURL, and I am pretty sure that no new sessions or download task are created after this point. How to stop all task from happening?
解决方案
I do not reccommend to use invalidateAndCancel method cause the queue and its identifier keeps invalidated and cannot be reused untill you reset the whole device.

NSURLSession class reference

I use this code to cancel all pending tasks.
- (void) cancelDownloadFiles
{

    [self.session getTasksWithCompletionHandler:^(NSArray *dataTasks, NSArray *uploadTasks, NSArray *downloadTasks) {

        for (NSURLSessionTask *_task in downloadTasks)
        {
            [_task cancel];

            id<FFDownloadFileProtocol> file = [self getFileDownloadInfoIndexWithTaskIdentifier:_task.taskIdentifier];

            [file.downloadTask cancel];

            // Change all related properties.
            file.isDownloading = NO;
            file.taskIdentifier = -1;
            file.downloadProgress = 0.0;

        }

    }];

    cancel = YES;
}


                        
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