Swift实现断点续传,Demo简单易懂,没有太多复杂模块和逻辑,完整体现断点续传的原理

ResumeFromBreakPoint

Swift实现断点续传,Demo简单易懂,没有太多复杂模块和逻辑,完整体现断点续传的原理
对应的Objective-C断点续传:https://github.com/whde/BreakPoint
Github:https://github.com/whde/ResumeFromBreakPoint

/*Objective-C*/pod 'BreakPoint', '~> 1.0.1'

WhdeBreakPoint

简单的网络请求队列管理类,简单的管理,不做太多复杂处理

/*创建请求,添加请求到数组中  WhdeSession请求失败,取消请求等需要从数组中移除*/static func asynDownload(urlStr:NSString, progress:ProgressBlock, success:SuccessBlock, failure:FailureBlock) ->WhdeSession

/*取消请求,移除数组中对应的请求*/static func cancel(urlStr:String)

/*暂停,即为取消请求*/static func pause(urlStr:String)

WhdeFileManager

断点续传专用的文件管理

/*根据NSURL获取存储的路径,文件不一定存在  文件名为Url base64转换*/static func filePath(url:NSURL) -> String

/*获取对应文件的大小*/static func fileSize(url:NSURL) -> UInt64

/*根据url删除对应的文件*/static func deleteFile(url:NSURL) ->Bool

WhdeSession

网络收发

/*创建请求,开始下载,设置已经下载的位置*/func asynDownload(urlStr:NSString, progress:ProgressBlock, success:SuccessBlock, failure:FailureBlock, callCancel:CallCancel) ->WhdeSession 

/*取消下载*/func cancel() -> Void

/*暂停下载即为取消下载*/func pause() -> Void 

/*出现错误,取消请求,通知失败*/internal func URLSession(session: NSURLSession, didBecomeInvalidWithError error: NSError?)

/*下载完成*/internal func URLSession(session: NSURLSession, task: NSURLSessionTask, didCompleteWithError error: NSError?)

/*接收到数据,将数据存储*/internal func URLSession(session: NSURLSession, dataTask: NSURLSessionDataTask, didReceiveData data: NSData) {     let response:NSHTTPURLResponse = dataTask.response as! NSHTTPURLResponse     if response.statusCode == 200 {         /*无断点续传时候,一直走200*/         self.progressBlock!(progress:(Float.init(dataTask.countOfBytesReceived)/Float.init(dataTask.countOfBytesExpectedToReceive)), receiveByte: dataTask.countOfBytesReceived, allByte: dataTask.countOfBytesExpectedToReceive)         self.save(data)     } else if response.statusCode == 206 {         /*断点续传后,一直走206*/         self.progressBlock!(progress:((Float.init(dataTask.countOfBytesReceived+Int64.init(startFileSize))/Float.init(dataTask.countOfBytesExpectedToReceive+Int64.init(startFileSize)))), receiveByte: dataTask.countOfBytesReceived, allByte: dataTask.countOfBytesExpectedToReceive);         self.save(data)     } }

/*存储数据,将offset标到文件末尾,在末尾写入数据,最后关闭文件*/func save(data:NSData) -> Void

使用

    var urlStr: String?="http://dlsw.baidu.com/sw-search-sp/soft/2a/25677/QQ_V4.1.1.1456905733.dmg"    /*开始下载      继续下载*/    @IBAction func start(sender: AnyObject) {        WhdeBreakPoint.asynDownload(urlStr!, progress: { (progress, receiveByte, allByte) in            self.progressView.progress = progress            self.progressLabel.text = "\(Int.init(progress*100))%"            }, success: { (filePath) in                print("success:"+(filePath as String))        }) { (filePath) in            print("success:"+(filePath as String))        }    }    /*根据Url暂停*/    @IBAction func pause(sender: AnyObject) {        WhdeBreakPoint.pause(urlStr!)    }    /*根据Url去删除文件*/    @IBAction func deleteFile(sender: AnyObject) {        WhdeFileManager.deleteFile(NSURL.init(string: urlStr!)!)    }