WP7 application how to post a local picture with facebook C# SDK?

I am developing a WP7 application and want to post a picture to the wall. I find that it need a URI for the picture but if I want to post a local picture from the mobile, what I should specify here or how can i get the uri for the l开发者_运维技巧ocal picture? Thanks a lot!

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The last time I looked at working with the Facebook SDK it wasn't possible to post a local photo to the user's wall; you had to have the photo hosted online somewhere already. However you can post to the user's photos section.

There is a forum post on the App Hub that gives the code for doing this. I think the Facebook C# SDK supports WP7, but I'm not sure if it will simplify this process any further.