iPhone: multi-part post using NSURLRequest
<p>I've seen a few articles, forum posts talking about uploading a file using NSURLRequest and NSURLConnection.  Some of the ones I've seen are:</p>

<ul>
<li><a href="http://forums.macrumors.com/showthread.php?t=427513" rel="nofollow">http://forums.macrumors.com/showthread.php?t=427513</a></li>
<li><a href="http://stackoverflow.com/questions/125306/how-can-i-upload-a-photo-to-a-server-with-the-iphone">http://stackoverflow.com/questions/125306/how-can-i-upload-a-photo-to-a-server-with-the-iphone</a></li>
<li><a href="http://www.cocoadev.com/index.pl?HTTPFileUploadSample" rel="nofollow">http://www.cocoadev.com/index.pl?HTTPFileUploadSample</a></li>
</ul>

<p>However, most of them don't include any sort of variables along with the file.  Say I wanted to post the following variables (and their values) along with a photo:</p>

<pre><code>user_id = 121
caption = this photo is awesome
thumbnail_x = 12
thumbnail_y = 0
thumbnail_w = 100
thumbnail_h = 200
photo = [file]
</code></pre>

<p>Is there a way to do this?</p>

<p>Or even better, is there already a class out there that builds on NSURLRequest that I could use?</p>
