据我所知，不能使用ASP.NET来完成，但是如果您使用Windows应用程序，请参阅:
-在.NET和C#中使用USB设备 [在C#程序中检测USB驱动器的移除 [

As far as I know, cannot be done using ASP.NET but if you use windows application, see:
- Working with USB devices in .NET and C#[^]
- Detecting USB Drive Removal in a C# Program[^]

Now if you detect when the phone is attached, you could start the download. This would of course mean that you have the application running which handles the detection.

您的意思是自动，您无法对aspx页面执行类似的操作.

编写Windows服务之类的东西，为驱动器缓冲并复制文件.

what do you mean by automatically, you can''t do anything like this with aspx pages.

write a windows service sort of thing, pool for the drive and copy the files.