title: Regex for hour, minute and second format HH:MM:SS
body: <p>Im trying to implement a Regex for HH:MM:SS, example:</p>
  
  <pre><code>07:15:30
  </code></pre>
  
  <p>But I can't get it work</p>
  
  <p>Right now Im using:</p>
  
  <pre><code>([01]?[0-9]|2[0-3]):[0-5][0-9]
  </code></pre>
  
  <p>Any clue?</p>