php - Regex to extract file extension from URL -

php - Regex to extract file extension from URL -

i looking regex match .js in next uri:

/foo/bar/file.js?cache_key=123

i'm writing function tries identify kind of file beingness passed in parameter. in case, file ends extension .js , javascript file. i'm working php , preg_match i'm assuming pcre compatible regular expression. i'll build on look , able check multiple file types beingness passed in uri isn't limited js, perhaps css, images, etc.

you can utilize combination of pathinfo , regular expression. pathinfo give extension plus ?cache_key=123, , can remove ?cache_key=123 regex matches ? , after it:

$url = '/foo/bar/file.js?cache_key=123'; echo preg_replace("#\?.*#", "", pathinfo($url, pathinfo_extension)) . "\n";

output:

js

input:

$url = 'my_style.css?cache_key=123';

output:

css

obviously, if need ., it's trivial add together file extension string.

eta: if want regex solution, trick:

function parseurl($url) { # takes lastly dot can find , grabs text after echo preg_replace("#(.+)?\.(\w+)(\?.+)?#", "$2", $url) . "\n"; } parseurl('my_style.css'); parseurl('my_style.css?cache=123'); parseurl('/foo/bar/file.js?cache_key=123'); parseurl('/my.dir.name/has/dots/boo.html?cache=123');

output:

css css js html

php regex