PHP code to detect file types based on file header information

Detecting file types function Checkfiletype ($fileName) { $file = fopen ($fileName, "RB"); $bin = Fread ($file, 2); Read-only 2 bytes Fclose ($file); c is an unsigned integer, the net search is C, signed integer, this will produce negative judgment is not normal $strInfo = @unpack ("C2chars", $bin); $typeCode = Intval ($strInfo [' chars1 ']. $strInfo [' chars2 ']); $fileType = "; Switch ($typeCode) { Case ' 255216 ': Return $typeCode. ' : ' .' JPG '; Break Case ' 7173 ': Return $typeCode. ' : ' .' GIF '; Break Case ' 13780 ': Return $typeCode. ' : ' .' PNG '; Break Case ' 6677 ': Return $typeCode. ' : ' .' BMP '; Break Case ' 7790 ': Return $typeCode. ' : ' .' EXE '; Break Case ' 7784 ': Return $typeCode. ' : ' .' Midi '; Break Case ' 8297 ': Return $typeCode. ' : ' .' RAR '; Break Default Return $typeCode. ' : ' .' Unknown '; Break } return $typeCode; } $file _name = ' 11.doc '; Echo Checkfiletype ($file _name); ?> Copy Code 2, according to the PHP file header information to verify the file type of the class /* Get the file type by filename * * $filename = "d:/1.png"; Echo Cfiletypecheck::getfiletype ($filename); Printing: PNG */ Class Cfiletypecheck { private static $_typelist=array (); private static $CheckClass =null; Private function __construct ($filename) { self::$_typelist= $this->gettypelist (); } /** * Process file Type mapping Relationship table * * * @param string $filename file type * @return string file type, not found returned: other */ Private Function _getfiletype ($filename) { $filetype = "other"; if (!file_exists ($filename)) throw new Exception ("No found file!"); $file = @fopen ($filename, "RB"); if (! $file) throw new Exception ("File refuse!"); $bin = Fread ($file, 15); Read-only 15 bytes each different file type, header information is not the same. Fclose ($file); $typelist =self::$_typelist; foreach ($typelist as $v) { $blen =strlen (Pack ("h*", $v [0]); Gets the number of file header tokens in bytes $tbin =substr ($bin, 0,intval ($blen)); Need to compare file header lengths if (Strtolower ($v [0]) ==strtolower (Array_shift (Unpack ("h*", $tbin)))) { return $v [1]; } } return $filetype; } /** * Get file header and File type mapping table * * * @return Array Array (' key ', value) ...) */ Public Function Gettypelist () { return Array (Array ("Ffd8ffe1", "jpg"), Array ("89504E47", "PNG"), Array ("47494638", "gif"), Array ("49492a00", "TIF"), Array ("424D", "BMP"), Array ("41433130", "DWG"), Array ("38425053", "PSD"), Array ("7b5c727466", "RTF"), Array ("3C3F786D6C", "xml"), Array ("68746d6c3e", "html"), Array ("44656c69766572792d646174", "eml"), Array ("cfad12fec5fd746f", "dbx"), Array ("2142444E", "PST"), Array ("D0cf11e0", "Xls/doc"), Array ("5374616e64617264204a", "MDB"), Array ("FF575043", "WPD"), Array ("252150532d41646f6265", "Eps/ps"), Array ("255044462d312e", "PDF"), Array ("E3828596", "PWL"), Array ("504b0304", "zip"), Array ("52617221", "rar"), Array ("57415645", "wav"), Array ("41564920", "avi"), Array ("2E7261FD", "Ram"), Array ("2e524d46", "rm"), Array ("000001BA", "mpg"), Array ("000001b3", "mpg"), Array ("6d6f6f76", "mov"), Array ("3026b2758e66cf11", "ASF"), Array ("4d546864", "mid")); } public static function Getfiletype ($filename) { if (!self:: $CheckClass) Self:: $CheckClass =new self ($filename); $class =self:: $CheckClass; Return $class->_getfiletype ($filename); } } $filename = "22.jpg"; echo $filename, "T", Cfiletypecheck::getfiletype ($filename), "RN"; $filename = "11.doc"; echo $filename, "T", Cfiletypecheck::getfiletype ($filename), "RN"; You can also detect this $filename = ' 22.jpg '; $extname = Strtolower (substr ($filename, Strrpos ($filename, '. ') + 1)); echo $extname. ' '; $file = @fopen ($filename, ' RB '); if ($file) { $str = @fread ($file, 0x400); Read the first 1024 bytes Echo substr ($str, 0, 4); @fclose ($file); } if (substr ($str, 0, 4) = = ' MThd ' && $extname! = ' txt ') { $format = ' mid '; } ElseIf (substr ($str, 0, 4) = = ' RIFF ' && $extname = = ' wav ') { $format = ' wav '; } ElseIf (substr ($str, 0, 3) = = "/xff/xd8/xff") { $format = ' jpg '; } ElseIf (substr ($str, 0, 4) = = ' GIF8 ' && $extname! = ' txt ') { $format = ' gif '; } ElseIf (substr ($str, 0, 8) = = "/x89/x50/x4e/x47/x0d/x0a/x1a/x0a") { $format = ' png '; } ElseIf (substr ($str, 0, 2) = = ' BM ' && $extname! = ' txt ') { $format = ' bmp '; } ElseIf ((substr ($str, 0, 3) = = ' CWS ' | | substr ($STR, 0, 3) = = ' FWS ') && $extname! = ' txt ') { $format = ' swf '; } ElseIf (substr ($str, 0, 4) = = "/xd0/xcf/x11/xe0") {//d0cf11e = = Docfile = = Microsoft Office Document if (substr ($str, 0x200,4) = = "/xec/xa5/xc1/x00" | | $extname = = ' Doc ') { $format = ' Doc '; } ElseIf (substr ($str, 0x200,2) = = "/x09/x08" | | $extname = = ' xls ') { $format = ' xls '; } elseif (substr ($str, 0x200,4) = = "/xfd/xff/xff/xff" | | $extname = = ' ppt ') { $format = ' ppt '; } } elseif (substr ($str, 0, 4) = = "pk/x03/x04") { $format = ' zip '; } elseif (substr ($str, 0, 4) = = ' rar! ' && $extname! = ' txt ') { $format = ' rar '; } elseif (substr ($str, 0, 4) = = "/x25pdf") { $format = ' pdf '; } elseif (substr ($str, 0, 3) = = "/x30/x82/x0a") { $format = ' cert '; } elseif (substr ($str, 0, 4) = = ' ITSF ' && $extname! = ' txt ') { $format = ' chm '; } elseif (substr ($str, 0, 4) = = "/X2ERMF") { $format = ' RM '; } elseif ($extname = = ' sql ') { $format = ' sql '; } elseif ($extname = = ' txt ') { $format = ' txt '; } Echo $format; ?> Copy Code

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