title: Regex that matches numbers, letters and dash but not the word net or NET
body: <p>So far I have</p>
  <pre><code>^[0-9a-zA-Z-]+$
  </code></pre>
  <p>and it works great matching numbers, letters and dashes but now I want to exclude the word net in both upper and lower case.</p>
  <p>More specifically,</p>
  <p><strong>Match:</strong></p>
  <p>net123</p>
  <p>123net</p>
  <p>word</p>
  <p>etc...</p>
  <p><strong>Don't Match:</strong></p>
  <p>NET</p>
  <p>net</p>
  <p>how can I add that detail to the Regex?</p>
  <p>Thanks!</p>