Best jQuery AJAX for multiple users
Uploading files using Ajax is not possible due to security reasons. There is a work around publishing files to an iframe, but you cannot select multiple files this way.
The solution lies in the flash. The two most common flash loaders are:
swfupload - http://swfupload.org/
uploadify - http://www.uploadify.com/ (jQuery only)
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plupload - http://www.plupload.com/
supports multiple uploads in every type except main html4
Allows you to upload files using HTML5, gears, flash, silverlight, BrowserPlus or plain to HTML4
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At this point, I would stay away from flash plugins. I would use HTML5 uploader instead : valums uploader
Of course - you can only select multiple files in modern browsers, otherwise - file by file. but hey - if a person doesn't care about updating to newer browsers - they probably don't know how to Ctrl + click anyway.
Flash does not send cookies correctly (it sends IE cookies even if you are using firefox or google chrome). So - you will lose cookies and therefore sessions. There is a workaround - send PHPSESSID in POST requests, but it just opens an open door for session commit.
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