Checking for file-extensions in PHP with Regular expressions

Question

I\'m reading all the files in a single directory and I want to filter on JPG,JPEG,GIF and PNG.

Both capital and small letters. Those are the only files to be accepte

Answer 1

There are a few ways of doing this.

Have you tried glob()?:

$files = glob("{$picsDir}/*.{gif,jpeg,jpg,png}", GLOB_BRACE);

Have you considered pathinfo()?:

$info = pathinfo($file);
switch(strtolower($info['extension'])) {
    case 'jpeg':
    case 'jpg':
    case 'gif':
    case 'png':
        $files[] = $file;
        break;
}

If you're insistant upon using the regular expression, there's no need to match the whole filename, just the extension. Use the $ token to match the end of the string, and use the i flag to denote case-insensitivity. Also, don't forget to use a delimiter in your expression, in my case "%":

$rex = '%\.(gif|jpe?g|png)$%i';