浏览器兼容性: PHP文件上传在IE和FF中$_FILES['userfile']['type']的表现形式

firefox image/jpeg image/bmp image/gif image/png
ie 6 image/pjpeg image/bmp image/gif image/x-png
ie 7 image/pjpeg image/bmp image/gif image/x-png
ie 8 image/pjpeg image/bmp image/gif image/x-png

附加一个判断脚本:

if ( !in_array($jpg_type, array("image/jpeg", "image/jpg", "image/jpe", "image/pjpeg")) && $jpg_type!= "image/gif" && !in_array("image/png", "image/x-png")) {}