php preg_match找到<img>标签，但没有gif扩展名

Question

I know how to find an img tag within a string but I need to exclude any img tag with gif extension in it. How do I use the negative in my preg_match? I only need the first image tag which does not contain .gif extension.

I currently have this:

  $text = html_entity_decode($text, ENT_QUOTES, 'UTF-8');
  $pattern = "/<img[^>]+\>/i";
  preg_match($pattern, $text, $matches);
  $text = $matches[0];

$text will give me the first tag, for e.g. <img src="something.gif" border="0" /> However, I do not want to accept .gif, so if the first is a gif, it will skip it and continue searching for other .

Please advise me how to change my code to it.

Thanks a bunch!

Answer 1

Don't do it that way. Attempting to parse HTML with regex is a task doomed to failure, since a slight increase in the complexity of the HTML or the requirement will make your regex unbelievably complicated.

The best way is to use a tool designed for the task: the DOMDocument class.

$dom = new DOMDocument;
$dom->loadHTML($text);

$images = $dom->getElementsByTagName('img');
foreach ($images as $image) {
    if (!substr($image->getAttribute('src'), -4) === '.gif') {
        break;
    }
}

// $image is now the first image that didn't end with .gif