可以自行查看flask 文档。
send file高效；
send from directory安全，且适用于静态资源交互。
都是实现相同的功能的。
send_file
send_from_directory
- send_from_directory send directory Flask filesend_from_directory send directory flask send_from_directory shared file directory libraries directory fatal error file libcudnn_cnn_infer file directory libcudnn directory macos node file shared file ogg_linux_x directory directory办法such file directory cannot find file file directory nginx after