ios - 如何暂停 NSURLSessionDownloadTask？

Question

这就是我使用 NSURLSessionDownloadTask 的方式:

    let sessionConfiguration = NSURLSessionConfiguration.defaultSessionConfiguration()
    let sessionManager = AFURLSessionManager(sessionConfiguration: sessionConfiguration)

    if let url = NSURL(string: URLString) {

        let request = NSURLRequest(URL: url)
        let sessionDownloadTask = sessionManager.downloadTaskWithRequest(request, progress: nil, destination: { (url, response) -> NSURL in

            self.createDirectoryAtPath(destinationPath)

            return destinationPath.URLByAppendingPathComponent(fileName)

            }, completionHandler: { response, url, error in

                completionBlock(error)
        })

        sessionDownloadTask.resume()
    }

我知道我可以调用 sessionDownloadTask.cancel() 和 sessionDownloadTask.resume()，但我需要在那里调用 .pause()，然后 .resume() 继续下载。可能吗？

Answer 1

NSURLSessionTask的这个方法

.suspend()

文档

A task, while suspended, produces no network traffic and is not subject to timeouts. A download task can continue transferring data at a later time. All other tasks must start over when resumed.