Progress bar on upload file

Hello,

I've created an Office add-in with Windows forms to let the user save and open files from our cloud solution.

So the user clicks on the button in the ribbon bar and opens a file from our server directly in Word.
When the user changes the file and wants to upload the changes, the whole file has to be uploaded. With large files this can be a long process.

That's why I would like to create a progress bar for the progress of the upload task.

I call a webservice and launch the setfile function. In a parameter I add the file in base64 format.

Is there a way I can follow this progress?