5 ways to get file extension in php

//Get file extension
$file = 'jbxue.com.php';
//Method 1
$path_info = pathinfo($file);
//print_r($path_info);
//echo "";
//echo $path_info['dirname'];
//echo "";
//echo $path_info['basename'];
echo "";
echo strtolower($path_info['extension']);
//Method 2
echo "---------------------";
$p = strrpos($file,'.'); //Get the last point The position of
echo strtolower(substr($file,$p+1));
//Method 3
echo "--------------- ------";
$arr = explode('.',$file);
echo strtolower($arr[count($arr)-1]);
//Method 4
echo "---------------------";
$arr = explode('.' ,$file);
echo strtolower(end($arr));
//Method 5
echo "----------------- ----";
preg_match('/.(w+)$/',$file,$extend);
echo strtolower($extend['1']);
//Method 6
echo "---------------------";
//strrchr($file,' .') from the last occurrence position to the last string
echo strtolower(substr(strrchr($file,'.'),1));

//by http://bbs.it-home.org
?>

Attachment: A little knowledge about extensions A file extension is a mechanism used by the operating system to identify a file format. Normally, an extension follows the main file name, separated by a delimiter. In a file name like "readme.txt", readme is the main file name and txt is the extension, indicating that the file is considered a plain text file.