title: Regex attribute out of tag
body: <p>I'm trying to regex src attribute (without its content/value) only and replace it with something else.</p>
  
  <p>It has to verify the HTML tag also (img in the example).</p>
  
  <p>Test data example:</p>
  
  <pre><code>&lt;img src="http://example.com" class="something" /&gt;
  </code></pre>
  
  <p>Now I need to get only "src" and replace it. Is it possible to get it as first/only match with lookbehind/lookahead in PHP?</p>