/// 设置下载并发数， 默认3
DownloadManager.default.maxDownloadCount = 3
/// 开启下载
public func download(model: DownloadModel)
/// 判断该文件是否下载完成
public func isCompletion(url: String) -> Bool
/// 判断该文件是否存在
public func isExistence(url: String) -> Bool
/// 根据url取消/暂停任务
public func cancelTask(url: String)
/// 取消/暂停所有任务
public func cancelAllTask()
/// 根据url删除资源
public func deleteFile(url: String)
/// 清空所有下载资源
public func deleteAllFile()
/// 获取下载的数据
public func getDownloadModels() -> [DownloadModel]
/// 获取下载完成的数据
public func getDownloadFinishModels() -> [DownloadModel]
/// 获取未下载完成的数据
public func getDownloadingModel() -> [DownloadModel]
/// 将未完成的下载状态改为.suspended
public func updateDownloadingStateWithSuspended()
/// 开启未完成的下载
public func updateDownloading()
/// 获取下载完成的文件路径
func getFile(url: String) -> String
/// 获取总缓存大小 单位：字节
public func getCacheSize() -> Double

/// 创建 DownloadModel
let model = DownloadModel()
model.model.name = "测试2"
model.model.url = "https://7xqhmn.media1.z0.glb.clouddn.com/femorning-20161106.mp4"

/// 下载
DownloadManager.default.download(model: model)

/// 注册通知
private func addNotification() {
        NotificationCenter.default.addObserver(self, selector: #selector(downLoadProgress(notification:)), name: DownloadProgressNotification, object: nil)
}

@objc private func downLoadProgress(notification: Notification) {
    /// 返回一个 DownloadDescModel
    if let model = notification.object as? DownloadDescModel {
        
    }
}

DownloadManager.default.maxDownloadCount = 3