如果我只有文件名，如何在PHP中获取文件扩展名？

Question

I have the path to an image file /files/uploads/1 but as you can see, I don't have an extension so I can't display the image. How can I get the extension of the file so I can display it? Thanks!

EDIT: Here is come code I have tried. BMP, PNG, JPG, JPEG and GIF are the only possible extensions, but $path ends up never getting assigned a value.

$exts = array('bmp','png','jpg','jpeg','gif');
foreach ($exts as $ext) {
    if (file_exists("/files/uploads/" . $id . "." . $ext)) {
        $path = "/files/uploads/" . $id . "." . $ext;
    }
}

Answer 1

Personally, I had a problem where I had an unnecessary slash (/) before my path in the file_exists check, but the solution to the question is still the same.

$exts = array('bmp','png','jpg','jpeg','gif','swf','psd','tiff','jpc','jp2','jpx','jb2','swc','iff','wbmp','xbm','ico');
foreach ($exts as $ext) {
    if (file_exists("files/uploads/" . $id . "." . $ext)) {
        $path = "/files/uploads/" . $id . "." . $ext;
    }
}