My scenario: in my company (more than 2.000 people), people were used to save files in many network shared folders, each with different set of users able to access it.
Now we are replacing the network folders with sharepoint, i.e. people are instructed to create SP document libraries, with the proper access rights, instead of using network folders as a shared storage.
Also, we have a lot of intranet web applications (ASP.NET), and it happens quite often that people have to upload files in these application.
Now the bad in using SP: users used to browse the shared folders and select the file to upload. Now with SP they need to download the file from SP user interface, save it somewhere and then upload it like they used to do. And that's bad.
Since SP can be accessed programmatically, it's reasonable to think to some "SharePoint document browser" component I can use within my applications to browse, select and use files (i.e. pick a file from SP and upload it to the application).
Obviously each user should be able to browse only the SP libraries he has access to. Also, it would be nice if this component could browse also the personal OneDrive of each user
What is the best approach to this issue? I read a lot (too much) of documentation about authentication and SPClient in NET, but cannot figure out the right combination to use. Our company is using both office365 and SP on premises (SPserver 2016): as a start, I'd like to access at least at the libraries created in office365 environment