OwnCloud API VB Net

I am trying to mount a project that I have in mind, and I need to synchronize the new files that I have in my OwnCloud a button, the new photos that have been included or those that have been replaced (this is my real problem) so I decide to upload photos in OwnCloud taking advantage of that infrastructure availability.

The fact is that the PROPFIND method is not very well controlled, so I try to find an API for VB Net that has everything armed, do you know any? Some WebDAV that is OwnCloud compatible

Try with WebClient and everything perfect, until you arrive at the time of comparing the dates of the servers on the server, with those that you had locally, or when you decided to list all the contents of that folder.

The same is not the most convenient method of making the application, I accept suggestions.