一个文件格式对应的数组 $mime_types = array( 'gif' => 'image/gif', 'jpg' => 'image/jpeg', 'jpeg' => 'image/jpeg', 'jpe' => 'image/jpeg', 'bmp' => 'image/bmp', 'png' => 'image/png', 'tif' => 'image/tiff', 'tiff' => 'image/tiff', 'pict' => 'image/x-pict', 'pic' => 'image/x-pict', 'pct' => 'image/x-pict', 'tif' => 'image/tiff', 'tiff' => 'image/tiff', 'psd' => 'image/x-photoshop', 'swf' => 'application/x-shockwave-flash', 'js' => 'application/x-javascript', 'pdf' => 'application/pdf', 'ps' => 'application/postscript', 'eps' => 'application/postscript', 'ai' => 'application/postscript', 'wmf' => 'application/x-msmetafile', 'css' => 'text/css', 'htm' => 'text/html', 'html' => 'text/html', 'txt' => 'text/plain', 'xml' => 'text/xml', 'wml' => 'text/wml', 'wbmp' => 'image/vnd.wap.wbmp', 'mid' => 'audio/midi', 'wav' => 'audio/wav', 'mp3' => 'audio/mpeg', 'mp2' => 'audio/mpeg', 'avi' => 'video/x-msvideo', 'mpeg' => 'video/mpeg', 'mpg' => 'video/mpeg', 'qt' => 'video/quicktime', 'mov' => 'video/quicktime', 'lha' => 'application/x-lha', 'lzh' => 'application/x-lha', 'z' => 'application/x-compress', 'gtar' => 'application/x-gtar', 'gz' => 'application/x-gzip', 'gzip' => 'application/x-gzip', 'tgz' => 'application/x-gzip', 'tar' => 'application/x-tar', 'bz2' => 'application/bzip2', 'zip' => 'application/zip', 'arj' => 'application/x-arj', 'rar' => 'application/x-rar-compressed', 'hqx' => 'application/mac-binhex40', 'sit' => 'application/x-stuffit', 'bin' => 'application/x-macbinary', 'uu' => 'text/x-uuencode', 'uue' => 'text/x-uuencode', 'latex'=> 'application/x-latex', 'ltx' => 'application/x-latex', 'tcl' => 'application/x-tcl', 'pgp' => 'application/pgp', 'asc' => 'application/pgp', 'exe' => 'application/x-msdownload', 'doc' => 'application/msword', 'rtf' => 'application/rtf', 'xls' => 'application/vnd.ms-excel', 'ppt' => 'application/vnd.ms-powerpoint', 'mdb' => 'application/x-msaccess', 'wri' => 'application/x-mswrite', );