Hello,
A little while ago, I began implementing dragging and dropping files from the Windows explorer to an application window for my current project.
After struggling to find the relevant information in the Microsoft documentation - including a broken link to a sample application - I decided to make my own application sample, so that the minimal knowledge to have for supporting dragging and dropping files in an application window is included in a short and easily buildable application:
https://github.com/alexGuntha/mindragndropwin
The most useful bit of info I found was here, under "Extracting the File Names from the Data Object":
https://docs.microsoft.com/en-us/windows/desktop/shell/datascenarios
If you have any issue with it, I'd like to have your feedback (is it really minimal? Isn't there a dirty thing still present in there?)
Personally I like drag'n'drop based tools, like Toycon, I think it's a good alternative to command-line only tools, and it got me started importing files in my current project without having to implement a fully-fledged file explorer :)
I hope it will help,
Have a good day :)