Ios AF2：取消批处理请求

我正在使用AFNetworking2代码来批处理请求。我从示例代码中复制粘贴，并将上载操作更改为下载。我需要取消控制器上的下载操作。我正在尝试实施取消：

    [[self.imagesQueue.operations 
filteredArrayUsingPredicate:[NSPredicate predicateWithBlock:^BOOL(id evaluatedObject, NSDictionary *bindings) 
{ return [evaluatedObject isKindOfClass:[AFHTTPRequestOperation class]]; }]] makeObjectsPerformSelector:@selector(cancel)];

批量请求的数量（下载图像）：

一系列启动和取消导致EXC_断点（代码=EXC_ARM_断点，子代码=0xdefe）：

---

有什么提示吗？

尝试将str声明为块变量（您正在块中访问它）：

在执行取消选择器之前，您还可以尝试检查操作是否已完成

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在view will dissides方法中，您可以调用映像队列上的cancelAllOperations来取消所有剩余的操作。

AFNetworking正在以巨大的速度变化。您的问题可能更适合github问题列表。

-(void) startDownloadImages {

    NSMutableArray *mutableOperations = [NSMutableArray array];
    //self.downloadOperations = [NSMutableArray array];
    for (NSString *str in _project.frames) {

        NSURLRequest *request =
        [[AFHTTPRequestSerializer serializer] requestWithMethod:@"GET"
                                                      URLString:str
                                                     parameters:nil];

        AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
        [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {

         NSLog(@"OK %@", str);


        } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
            NSLog(@"FAILS %@", str);
        }];

        [mutableOperations addObject:operation];
    }

    NSArray *operations =
    [AFURLConnectionOperation batchOfRequestOperations:mutableOperations
                                         progressBlock:^(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations) {
        NSLog(@"%lu of %lu complete", (unsigned long)numberOfFinishedOperations, (unsigned long)totalNumberOfOperations);
    } completionBlock:^(NSArray *operations) {
        NSLog(@"All operations in batch complete");

    }];

    self.imagesQueue = [[NSOperationQueue alloc] init];
    self.imagesQueue.name = @"com.imagesqueue";
    self.imagesQueue.maxConcurrentOperationCount = 1;

    [self.imagesQueue addOperations:operations waitUntilFinished:NO];
    //[[NSOperationQueue mainQueue] addOperations:operations waitUntilFinished:NO];
}

libdispatch.dylib`dispatch_group_leave:
    0x37e1e7d8:  dmb    ishst
    0x37e1e7dc:  ldrex  r1, [r0, #40]
    0x37e1e7e0:  adds   r1, #1
    0x37e1e7e2:  strex  r2, r1, [r0, #40]
    0x37e1e7e6:  cmp    r2, #0
    0x37e1e7e8:  bne    0x37e1e7dc                ; dispatch_group_leave + 4
    0x37e1e7ea:  cmp.w  r1, #4294967295
    0x37e1e7ee:  ble    0x37e1e7fe                ; dispatch_group_leave + 38
    0x37e1e7f0:  mvn    r2, #2147483648
    0x37e1e7f4:  cmp    r1, r2
    0x37e1e7f6:  it     eq
    0x37e1e7f8:  beq.w  0x37e21df8                ; _dispatch_group_wake
    0x37e1e7fc:  bx     lr
    0x37e1e7fe:  trap   
    0x37e1e800:  nop    
    0x37e1e802:  nop 

__block NSString *str;

for (str in _project.frames) {