How do I make my application display whatever drag graphic is used by the source?

When you drag a picture from Firefox to Windows Explorer, Explorer shows Fi开发者_如何转开发refox's drag graphic. How does he do it?

Illustration: http://www.youtube.com/watch?v=3rliNPuKh58 (The video capture is not entirely accurate - the mouse cursor is shown as an arrow at all times when it in fact changes between the default drag and drop cursor and the slashed circle.)

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D'oh, sorry. I only gave it a quick glance. You'll have to use the shell COM interfaces (IDropSource, IDragSourceHelper) to achieve this.