iPhone: cached profile images from the web - how to find out that remote image changed?

Posted by Stefan Klumpp on Stack Overflow See other posts from Stack Overflow or by Stefan Klumpp
Published on 2010-05-29T14:48:26Z Indexed on 2010/05/29 14:52 UTC
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iphone

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image

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facebook

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caching

I'm loading profile pictures from Facebook, cache them on disk and load them into cells of a UITableView.

Now I'm wondering, how I can find out when someone has changed his/her profile picture on Facebook that I have to load the new image from the web instead of using the one cached disk.

The url of the image is always the same. Is there a lightweight way of doing this without downloading the image and comparing it to the local file?

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