本文实例讲述了php获取文件mime类型的方法。分享给大家供大家参考。具体如下:
1.使用 mime_content_type 方法
string mime_content_type ( string $filename )
Returns the MIME content type for a file as determined by using information from the magic.mime file.
<?php $mime_type = mime_content_type('1.jpg'); echo $mime_type; // image/jpeg ?>
但此方法在 php5.3 以上就被废弃了,官方建议使用 fileinfo 方法代替。
2.使用 Fileinfo 方法 (官方推荐)
使用fileinfo需要安装php_fileinfo扩展。
如已安装可以在extension_dir目录下找到php_fileinfo.dll(windows),fileinfo.so(linux)
打开php.ini,把extension=php_fileinfo.dll前的";"去掉,然后重启apache。
<?php $fi = new finfo(FILEINFO_MIME_TYPE); $mime_type = $fi->file('1.jpg'); echo $mime_type; // image/jpeg ?>
3.使用 image_type_to_mime_type 方法(只能处理图象类型)
使用exif_imagetype方法需要安装php_exif扩展,并需要安装php_mbstring扩展
如已安装可以在extension_dir目录下找到php_exif.dll(windows),exif.so(linux)
打开php.ini,把 extension=php_mbstring.dll, extension=php_exif.dll 前的","去掉,然后重启apache
<?php $image = exif_imagetype('1.jpg'); $mime_type = image_type_to_mime_type($image); echo $mime_type; // image/jpeg ?>
Tips:如果使用文件名的后缀来判断,因为文件后缀是可以修改的,所以使用文件后缀来判断会不准确。
希望本文所述对大家的php程序设计有所帮助。

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