php准确获取文件MIME类型的方法

本文实例讲述了php准确获取文件MIME类型的方法。分享给大家供大家参考。具体实现方法如下：

<?php$mime = array (    //applications    'ai'  => 'application/postscript',    'eps'  => 'application/postscript',    'exe'  => 'application/octet-stream',    'doc'  => 'application/vnd.ms-word',    'xls'  => 'application/vnd.ms-excel',    'ppt'  => 'application/vnd.ms-powerpoint',    'pps'  => 'application/vnd.ms-powerpoint',    'pdf'  => 'application/pdf',    'xml'  => 'application/xml',    'odt'  => 'application/vnd.oasis.opendocument.text',    'swf'  => 'application/x-shockwave-flash',    // archives    'gz'  => 'application/x-gzip',    'tgz'  => 'application/x-gzip',    'bz'  => 'application/x-bzip2',    'bz2'  => 'application/x-bzip2',    'tbz'  => 'application/x-bzip2',    'zip'  => 'application/zip',    'rar'  => 'application/x-rar',    'tar'  => 'application/x-tar',    '7z'  => 'application/x-7z-compressed',    // texts    'txt'  => 'text/plain',    'php'  => 'text/x-php',    'html' => 'text/html',    'htm'  => 'text/html',    'js'  => 'text/javascript',    'css'  => 'text/css',    'rtf'  => 'text/rtf',    'rtfd' => 'text/rtfd',    'py'  => 'text/x-python',    'java' => 'text/x-java-source',    'rb'  => 'text/x-ruby',    'sh'  => 'text/x-shellscript',    'pl'  => 'text/x-perl',    'sql'  => 'text/x-sql',    // images    'bmp'  => 'image/x-ms-bmp',    'jpg'  => 'image/jpeg',    'jpeg' => 'image/jpeg',    'gif'  => 'image/gif',    'png'  => 'image/png',    'tif'  => 'image/tiff',    'tiff' => 'image/tiff',    'tga'  => 'image/x-targa',    'psd'  => 'image/vnd.adobe.photoshop',    //audio    'mp3'  => 'audio/mpeg',    'mid'  => 'audio/midi',    'ogg'  => 'audio/ogg',    'mp4a' => 'audio/mp4',    'wav'  => 'audio/wav',    'wma'  => 'audio/x-ms-wma',    // video    'avi'  => 'video/x-msvideo',    'dv'  => 'video/x-dv',    'mp4'  => 'video/mp4',    'mpeg' => 'video/mpeg',    'mpg'  => 'video/mpeg',    'mov'  => 'video/quicktime',    'wm'  => 'video/x-ms-wmv',    'flv'  => 'video/x-flv',    'mkv'  => 'video/x-matroska'    );function _getMimeDetect() {  if (class_exists('finfo')) {    return 'finfo';  } else if (function_exists('mime_content_type')) {    return 'mime_content_type';  } else if ( function_exists('exec')) {    $result = exec('file -ib '.escapeshellarg(__FILE__));    if ( 0 === strpos($result, 'text/x-php') OR 0 === strpos($result, 'text/x-c++')) {      return 'linux';    }    $result = exec('file -Ib '.escapeshellarg(__FILE__));    if ( 0 === strpos($result, 'text/x-php') OR 0 === strpos($result, 'text/x-c++')) {      return 'bsd';    }  }  return 'internal';}function _getMimeType($path) {  global $mime;  $fmime = _getMimeDetect();  switch($fmime) {    case 'finfo':      $finfo = finfo_open(FILEINFO_MIME);      if ($finfo)         $type = @finfo_file($finfo, $path);      break;    case 'mime_content_type':      $type = mime_content_type($path);      break;    case 'linux':      $type = exec('file -ib '.escapeshellarg($path));      break;    case 'bsd':      $type = exec('file -Ib '.escapeshellarg($path));      break;    default:      $pinfo = pathinfo($path);      $ext = isset($pinfo['extension']) ? strtolower($pinfo['extension']) : '';      $type = isset($mime[$ext]) ? $mime[$ext] : 'unkown';      break;  }  $type = explode(';', $type);  //需要加上这段，因为如果使用mime_content_type函数来获取一个不存在的$path时会返回'application/octet-stream'  if ($fmime != 'internal' AND $type[0] == 'application/octet-stream') {    $pinfo = pathinfo($path);     $ext = isset($pinfo['extension']) ? strtolower($pinfo['extension']) : '';    if (!empty($ext) AND !empty($mime[$ext])) {      $type[0] = $mime[$ext];    }  }  return $type[0];}$path = '1.txt'; //实际上当前路径并不存在1.txtvar_dump(_getMimeType($path));/*End of php*/