php method to get the file mime type
1. Use the mime_content_type method
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 ?>
But this method was abandoned in php5.3 or above, and the official recommendation is to use the fileinfo method instead.
2. Use Fileinfo method (official recommendation)
Using fileinfo requires installing the php_fileinfo extension.
If it has been installed, it can be found in the extension_dir directory php_fileinfo.dll(windows), fileinfo.so(linux)
Open php.ini and change the " in front of extension=php_fileinfo.dll ;"Remove it and restart apache.
<?php $fi = new finfo(FILEINFO_MIME_TYPE); $mime_type = $fi->file('1.jpg'); echo $mime_type; // image/jpeg ?>
3. Use the image_type_to_mime_type method (can only handle image types)
Using the exif_imagetype method requires installing the php_exif extension and the php_mbstring extension
If it has been installed, it can be in the extension_dir directory Find php_exif.dll(windows),exif.so(linux)
Open php.ini, remove the "," before extension=php_mbstring.dll, extension=php_exif.dll, and then restart apache
<?php $image = exif_imagetype('1.jpg'); $mime_type = image_type_to_mime_type($image); echo $mime_type; // image/jpeg ?>
Tips:If you use the suffix of the file name to judge, because the file suffix can be modified, using the file suffix to judge will not be accurate.
The above introduces the method of obtaining the mime type of the file in PHP, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.

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