问题描述
这是一个问题，您可以在网上随处阅读，并获得各种答案:
This is a question you can read everywhere on the web with various answers:
$ext = end(explode('.', $filename));
$ext = substr(strrchr($filename, '.'), 1);
$ext = substr($filename, strrpos($filename, '.') + 1);
$ext = preg_replace('/^.*\.([^.]+)$/D', '$1', $filename);
$exts = split("[/\\.]", $filename);
$n = count($exts)-1;
$ext = $exts[$n];
等
但是，总有最佳方法"，它应该在堆栈溢出中.
However, there is always "the best way" and it should be on Stack Overflow.
推荐答案
来自其他脚本语言的人们总是认为它们更好，因为它们具有内置功能而不是PHP(我现在正在研究Pythonista: -)).
People from other scripting languages always think theirs is better because they have a built-in function to do that and not PHP (I am looking at Pythonistas right now :-)).
事实上，它确实存在，但是很少有人知道.见面 pathinfo() :
In fact, it does exist, but few people know it. Meet pathinfo():
$ext = pathinfo($filename, PATHINFO_EXTENSION);
这是快速且内置的. pathinfo()可以根据传递给它的常量为您提供其他信息，例如规范路径.
This is fast and built-in. pathinfo() can give you other information, such as canonical path, depending on the constant you pass to it.
请记住，如果您希望能够处理非ASCII字符，则需要先设置语言环境.例如:
Remember that if you want to be able to deal with non ASCII characters, you need to set the locale first. E.G:
setlocale(LC_ALL,'en_US.UTF-8');
此外，请注意，这并未考虑文件内容或mime类型，您只获得了扩展名.但这就是您要的.
Also, note this doesn't take into consideration the file content or mime-type, you only get the extension. But it's what you asked for.
最后，请注意，这仅适用于文件路径，不适用于使用PARSE_URL覆盖的URL资源路径.
Lastly, note that this works only for a file path, not a URL resources path, which is covered using PARSE_URL.
享受
这篇关于如何在PHP中获得文件扩展名?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！