So when your Unity application wants to react to dropped files (on windows builds) it has to react to the WM_DROPFILES message that is send to the window message queue. The main issue is that Unity is closed source and the main message pump of the application belongs to Unity's native code we don't have access to. This would make Unity more valueable for webtool-development, but as already said there is just a minority of people that would need something like that. Well it would be nice to have something like that in the webplayer together with a secure interface to the dropped data (only read access). Well Unity could add such a feature in the future, but it's really something that almost nobody needs. Of course this is not an optimal solution, but Unity isn't designed for office-application development. I guess it would be easier to create a native code plugin which creates another window which will accept drag&drop opperations and hand over this information to Unity. I'm a bit confused why you want to do such an app as Unity application? That seems to be much easier when you just use C# / C++ and the windows API (in case you want to target windows which can't be determined from your question).Īs i said in the comment of the question above it could be possible to kind of hack into the message queue of your application window, but that's not a nice solution.

Drag and drop desktop app builder