Ios 如何使用URLSessionManager取消NSURLSessionDownloadTask？

我想用AFURLSessionManager方法

@selector（collectionAction）

下载一些图片：

数字在不断滚动，然后我的iPhone几乎停止工作。因此，如果其中任何一项任务失败，我想取消这些任务。但是使用

[manager invalidateSessionCancelingTasks:YES]或
[manager.operationQueue cancelAllOperations]我有另一个错误

2014-12-02 11:34:13.040 MoneyPower[11216:1204788] *** Terminating app due to uncaught     exception 'NSInternalInconsistencyException', reason: 'An instance 0x17947310 of class __NSCFLocalDownloadTask was deallocated while key value observers were still registered with it. Current observation info: <NSKeyValueObservationInfo 0x179449e0> (<NSKeyValueObservance 0x17944b40: Observer: 0x1785d3a0, Key path: state, Options: <New: YES, Old: YES, Prior: NO> Context: 0x3992cc, Property: 0x179462a0>)'
*** First throw call stack:(0x227ddc1f 0x2ffc4c8b 0x227ddb65 0x23485c25 0x2ffded5f 0x2229cb89 0x2ffded5f 0x3055fae1 0x3055fae1 0x836e29 0x8312c9 0x838567 0x839891 0x30685e31 0x30685b84)libc++abi.dylib: terminating with uncaught exception of type NSException

2014-12-02 11:34:13.040 MoneyPower[11216:1204788]***由于未捕获的异常“NSInternalInconsistencyException”而终止应用程序，原因是：“在仍向其注册键值观察者的同时，释放了类u NSCFLocalDownloadTask的实例0x17947310。”。当前观测信息：（）'
***第一次抛出调用堆栈：（0x227ddc1f 0x2ffc4c8b 0x227ddb65 0x23485c25 0x2ffded5f 0x2229cb89 0x2ffded5f 0x3055fae1 0x836e29 0x8312c9 0x838567 0x839891 0x30685e31 0x30685b84）libc++abi.dylib：以NSException类型的未捕获异常终止

我该怎么处理呢？
嗨，我遇到了和你一样的问题。你解决了吗？你是怎么做到的？提前谢谢。@Lilac很抱歉告诉你，我没有找到任何解决办法，我只是放手了。没关系。我通过使用NSURLSession而不使用AFNetworking来解决此问题。：P
2014-12-02 11:34:09.711 MoneyPower[11216:1204579] File downloaded to: (null)
2014-12-02 11:34:12.936 MoneyPower[11216:1204579] File downloaded to: (null)
2014-12-02 11:34:12.951 MoneyPower[11216:1204579] File downloaded to: (null)

2014-12-02 11:34:13.040 MoneyPower[11216:1204788] *** Terminating app due to uncaught     exception 'NSInternalInconsistencyException', reason: 'An instance 0x17947310 of class __NSCFLocalDownloadTask was deallocated while key value observers were still registered with it. Current observation info: <NSKeyValueObservationInfo 0x179449e0> (<NSKeyValueObservance 0x17944b40: Observer: 0x1785d3a0, Key path: state, Options: <New: YES, Old: YES, Prior: NO> Context: 0x3992cc, Property: 0x179462a0>)'
*** First throw call stack:(0x227ddc1f 0x2ffc4c8b 0x227ddb65 0x23485c25 0x2ffded5f 0x2229cb89 0x2ffded5f 0x3055fae1 0x3055fae1 0x836e29 0x8312c9 0x838567 0x839891 0x30685e31 0x30685b84)libc++abi.dylib: terminating with uncaught exception of type NSException