CI支持各种文件上传-文件类型，Linux + window

$mimes = array( 'hqx' => 'application/mac-binhex40',

'cpt' => 'application/mac-compactpro',

'csv' => array('text/x-comma-separated-values', 'text/comma-separated-values', 'application/octet-stream', 'application/vnd.ms-excel', 'application/x-csv', 'text/x-csv', 'text/csv', 'application/csv', 'application/excel', 'application/vnd.msexcel'),

'bin' => 'application/macbinary',

'dms' => 'application/octet-stream',

'lha' => 'application/octet-stream',

'lzh' => 'application/octet-stream',

'exe' => array('application/octet-stream', 'application/x-msdownload'),

'class' => 'application/octet-stream',

'psd' => 'application/x-photoshop',

'so' => 'application/octet-stream',

'sea' => 'application/octet-stream',

'dll' => 'application/octet-stream',

'oda' => 'application/oda',

'ai' => 'application/postscript',

'eps' => 'application/postscript',

'ps' => 'application/postscript',

'smi' => 'application/smil',

'smil' => 'application/smil',

'mif' => 'application/vnd.mif',

'wbxml' => 'application/wbxml',

'wmlc' => 'application/wmlc',

'dcr' => 'application/x-director',

'dir' => 'application/x-director',

'dxr' => 'application/x-director',

'dvi' => 'application/x-dvi',

'gtar' => 'application/x-gtar',

'gz' => 'application/x-gzip',

'php' => 'application/x-httpd-php',

'php4' => 'application/x-httpd-php',

'php3' => 'application/x-httpd-php',

'phtml' => 'application/x-httpd-php',

'phps' => 'application/x-httpd-php-source',

'js' => 'application/x-javascript',

'swf' => array('application/x-shockwave-flash','application/octet-stream'),

'sit' => 'application/x-stuffit',

'tar' => 'application/x-tar',

'tgz' => array('application/x-tar', 'application/x-gzip-compressed'),

'xhtml' => 'application/xhtml+xml',

'xht' => 'application/xhtml+xml',

'rar' => array('application/x-rar-compressed', 'application/x-rar', 'application/rar', 'application/octet-stream'),

'zip' => array('application/x-zip', 'application/zip', 'application/x-zip-compressed', 'application/octet-stream'),

'mid' => 'audio/midi',

'midi' => 'audio/midi',

'mpga' => 'audio/mpeg',

'mp2' => 'audio/mpeg',

'mp3' => array('audio/mpeg', 'audio/mpg', 'audio/mpeg3', 'audio/mp3'),

'aif' => 'audio/x-aiff',

'aiff' => 'audio/x-aiff',

'aifc' => 'audio/x-aiff',

'ram' => 'audio/x-pn-realaudio',

'rm' => 'audio/x-pn-realaudio',

'rpm' => 'audio/x-pn-realaudio-plugin',

'ra' => 'audio/x-realaudio',

'rv' => 'video/vnd.rn-realvideo',

'wav' => array('audio/x-wav', 'audio/wave', 'audio/wav'),

'bmp' => array('image/bmp', 'image/x-windows-bmp'),

'gif' => 'image/gif',

'jpeg' => array('image/jpeg', 'image/pjpeg','application/octet-stream'),

'jpg' => array('image/jpeg', 'image/pjpeg','application/octet-stream'),

'jpe' => array('image/jpeg', 'image/pjpeg','application/octet-stream'),

'png' => array('image/png', 'image/x-png','application/octet-stream'),

'tiff' => 'image/tiff',

'tif' => 'image/tiff',

'css' => 'text/css',

'html' => 'text/html',

'htm' => 'text/html',

'shtml' => 'text/html',

'txt' => 'text/plain',

'text' => 'text/plain',

'log' => array('text/plain', 'text/x-log'),

'rtx' => 'text/richtext',

'rtf' => 'text/rtf',

'xml' => 'text/xml',

'xsl' => 'text/xml',

'mpeg' => 'video/mpeg',

'mpg' => 'video/mpeg',

'mpe' => 'video/mpeg',

'qt' => 'video/quicktime',

'mov' => 'video/quicktime',

'avi' => 'video/x-msvideo',

'movie' => 'video/x-sgi-movie',

'pdf' => array('application/pdf', 'application/x-download', 'application/octet-stream'),

'doc' => array('application/msword','application/octet-stream'),

'docx' => array('application/vnd.openxmlformats-officedocument.wordprocessingml.document', 'application/zip', 'application/msword','application/x-zip', 'application/octet-stream'),

'xls' => array('application/excel', 'application/vnd.ms-excel', 'application/msexcel', 'application/x-zip','application/msword', 'application/octet-stream'),

'xlsx' => array('application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', 'application/zip', 'application/x-zip', 'application/vnd.ms-excel', 'application/octet-stream'),

'ppt' => array('application/powerpoint', 'application/vnd.ms-powerpoint', 'application/octet-stream', 'application/vnd.openxmlformats-officedocument.presentationml.presentation'),

'pptx' => array('application/powerpoint', 'application/vnd.ms-powerpoint', 'application/octet-stream', 'application/vnd.openxmlformats-officedocument.presentationml.presentation'),

'word' => array('application/msword', 'application/octet-stream'),

'xl' => 'application/excel',

'eml' => 'message/rfc822',

'json' => array('application/json', 'text/json')

);