Trouble in posting the String and Image File at a time from a dektop application to a webpage.

Question

I am trying to POST any image, its description, and remarks if any; entered by an application user to a webpage. I can upload such data either string or a file at a time. I want to upload both of them at a time, for which I need some assistance. Can any one give me any clues? There is a post type called MultiPart posting in asp.net but i wasn't able to use it through vb.net.