在swift中从weburl识别资源名称和扩展名

你可以用 downloadTask.response?.suggestedFilename 从下面 func

 func URLSession(session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingToURL location: NSURL) {
        print(downloadTask.response?.suggestedFilename as Any)
        print(downloadTask.response?.mimeType as Any)

    }