PHP custom class for detecting file types via file header

/* Get the file type by filename * * @author chengmo* * @version 0.1 * $filename = "d:/1.png"; Echo Cfiletypecheck::getfiletype ($filename); Printing: PNG * Edit bbs.it-home.org */ 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 $filetype; } /** * Get file header and File type mapping table * * * @return Array Array (array (key,value) ...) */ Public Function Gettypelist () { return Array (Array ("Ffd8ffe1", "jpg"), Array ("89504E47", "PNG"), Array ("47494638", "gif"), Array ("49492a00", "TIF"), Array ("424D", "BMP"), Array ("41433130", "DWG"), Array ("38425053", "PSD"), Array ("7b5c727466", "RTF"), Array ("3C3F786D6C", "xml"), Array ("68746d6c3e", "html"), Array ("44656c69766572792d646174", "eml"), Array ("cfad12fec5fd746f", "dbx"), Array ("2142444E", "PST"), Array ("D0cf11e0", "Xls/doc"), Array ("5374616e64617264204a", "MDB"), Array ("FF575043", "WPD"), Array ("252150532d41646f6265", "Eps/ps"), Array ("255044462d312e", "PDF"), Array ("E3828596", "PWL"), Array ("504b0304", "zip"), Array ("52617221", "rar"), Array ("57415645", "wav"), Array ("41564920", "avi"), Array ("2E7261FD", "Ram"), Array ("2e524d46", "rm"), Array ("000001BA", "mpg"), Array ("000001b3", "mpg"), Array ("6d6f6f76", "mov"), Array ("3026b2758e66cf11", "ASF"), Array ("4d546864", "mid")); } public static function Getfiletype ($filename) { if (!self:: $CheckClass) Self:: $CheckClass =new self ($filename); $class =self:: $CheckClass; Return $class->_getfiletype ($filename); } } ?> Copy Code

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