title: Javascript string verification using Regex
body: <p>How can I format this so it only checks if my string starts with the letter "a" or "b" and also accepts misc. characters after this (numbers or letters)? <br> <br> Just need to make sure it starts with the letter a or b, the rest is ok and will have more characters.</p>
  
  <pre><code>mystring.match(/^D\d{22}$/i
  </code></pre>