title: Regular expression to match a united states phone pattern
body: <p>I want to validate a United States phone number, this is what I have so far:</p>
  
  <pre><code>var numberRegex = /^\(?([0-9]{3})\)?[-. ]?([0-9]{3})[-. ]?([0-9]{4})$/
  </code></pre>
  
  <p>My problem with this is that this allows single bracket.  </p>
  
  <p>This will allow to pass an opening parenthesis without a closing one like this: <code>(111-121-1212</code>.  </p>
  
  <p>Does anyone have a regex script that will match a U.S phone number and account for brackets?</p>