The wp_check_filetype() WordPress PHP function fetches the file type from a file name. It can be helpful when you need to determine the extension or MIME type of a particular file.
Usage
Here’s a general usage of the function with a custom example showing its input and output:
$filetype = wp_check_filetype('document.pdf');
echo $filetype['ext']; // will output "pdf"
Parameters
- $filename (string) [Required]: This is the file name or path.
- $mimes (string[]) [Optional]: This is an array of allowed MIME types, keyed by their file extension regex. The default value is null, which defaults to the result of get_allowed_mime_types().
More information
See WordPress Developer Resources: wp_check_filetype() Please note that the wp_check_filetype() function was implemented in WordPress version 2.5.0.
Examples
Checking a JPEG Image
In this example, we are checking the filetype of a JPEG image.
$filetype = wp_check_filetype('image.jpeg');
echo $filetype['ext']; // will output "jpeg"
Checking a GIF Image
Here, we want to find out the filetype of a GIF image.
$filetype = wp_check_filetype('animation.gif');
echo $filetype['ext']; // will output "gif"
Checking a Word Document
We can also check the filetype of a Word document with this function.
$filetype = wp_check_filetype('report.docx');
echo $filetype['ext']; // will output "docx"
Checking an MP3 Audio File
If we need to determine the filetype of an MP3 audio file, we can do so as follows.
$filetype = wp_check_filetype('song.mp3');
echo $filetype['ext']; // will output "mp3"
Checking a Video File
Finally, we can check the filetype of a video file like this.
$filetype = wp_check_filetype('movie.mp4');
echo $filetype['ext']; // will output "mp4"
Remember, in all these examples, if the file does not match a MIME type, the output will be false.