I am experiencing inconsistencies with regard to multiple file upload in Safari 5.1 on Windows Vista (haven't tried other platforms). The input element has the multiple flag to allow selection of multiple files. The problem occurs when the user does actually select more then one file. In this case, each File has a size attribute of 0. If (still with the multiple flag), the user only chooses one file, the size attribute correctly contains the file size.
The problem can be seen in the following example. Test and view the output of both a single file selection and a multiple file selection. (You will need to reset between tests). JsFiddle Test
Does anyone know of a workaround?
IT's a Safari bug. No solution for the moment. here is the test i did http://jsfiddle.net/rHd26/6/
Workaround for us was to remove multiple option... we got file size of 0, but we also got bad filenames with leading strange character added to the filename. Maybe that is why we get 0 in the size: because the first property (filename) is not split correctly with the presence of that bad character at the end of the filename.
Check this hack.
It explains in detail how to remove multiple option for Safari only, leaving other browsers alone.
Any workarounds for the Safari HTML5 multiple file upload bug?
A variation of this issue also seems to have infected mobile Safari on iOS 7, which just released. If you have a "multiple" file input field, and select a video, then the File API returns a file size of 0. Indeed the jsfiddle at the top of this page, reproduces this.
Selecting one or more photos with the "multiple" option is fine - this only affects videos.
来源：https://stackoverflow.com/questions/7231054/file-input-size-issue-in-safari-for-multiple-file-selection