ALDownloadManager包含了断点续传，多文件顺序下载，多文件同时下载

同时下载

顺序下载

外层调用： 单文件下载

ALDownloadManager.shared.download(url: self.testUrl)?.downloadProgress(nil).downloadResponse(nil)
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多文件同时下载

ALDownloadManager.shared.changeDownloadState()
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多文件顺序下载

 ALDownloadManager.shared.changeWaitState(completeClose: nil)
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具体实现： 下载方法（默认断点续传）

   func download() {if let resumeData = cancelledData {let destination = createDestination(destinationPath: destinationPath)downloadRequest = manager?.download(resumingWith: resumeData, to: destination).response(completionHandler: { [weak self] (defresponse) inself?.cancelledData = defresponse.resumeData}).downloadProgress(closure: { (progress) inself.progress = progress}).response(completionHandler: { (defaultResponse) inself.respons = defaultResponse})}else{let destination = createDestination(destinationPath: destinationPath)if let url = downloadurl {downloadRequest = manager?.download(url, method: .get, parameters: nil, encoding: JSONEncoding.default, headers: nil, to: destination).response(completionHandler: { [weak self] (defresponse) inself?.cancelledData = defresponse.resumeData}).downloadProgress(closure: { (progress) inself.progress = progress}).response(completionHandler: { (defaultResponse) inself.respons = defaultResponse})}}self.state = ALDownloadState.Download}
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cancelledData 下载失败时的数据，恢复下载时需要用到 downloadRequest 每次下载时重新赋值，保证downloadRequest为最新值

取消下载

   func cancel() {downloadRequest?.cancel()self.state = ALDownloadState.Cancel}
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Alamofire的取消下载，加上下载状态的改变

挂起

   func hangup() {downloadRequest?.cancel()self.state = ALDownloadState.Wait}
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下载任务挂起（等待下载）： 顺序下载时用到

同时下载

   func changeDownloadState() {self.downloadInfoArray = self.downloadInfoArray?.map({ (info) -> ALDownloadInfo inif  info.state == ALDownloadState.Download || info.state == ALDownloadState.Completed{}else{info.download()}return info})}
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正在下载和已经下载完成的任务保持，其余任务改变为下载状态

这里重点说下顺序下载

   func changeWaitState(completeClose: ALDownloadCompleteClose?) {self.completeClose = completeClosevar isDownloadFirst = falseself.downloadInfoArray = self.downloadInfoArray?.map({ (info) -> ALDownloadInfo inif isDownloadFirst == false {if info.state == ALDownloadState.Download {isDownloadFirst = truereturn info}}if info.state == ALDownloadState.Completed {}else{info.hangup()}return info})if isDownloadFirst == false {resumeFirstWillResume()}}
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如果有任务下载，下载中的第一个任务保持下载状态，其余改变为等待下载；如果没有任务下载，将所有任务改变为等待下载，再下载第一个等待任务，这是我的思路，有更好方法的麻烦告知我

就想要?? 欢迎戳这里 哈哈哈

发现bug或好的建议欢迎 issues or Email Yvente@163.com