title: ASP.Net Validation Expressions for Phone Numbers
body: <p>I need a Validation Expression to validate an Egyptian mobile number as an input in my form.</p>
  
  <p>Egyptian Mobile Number: </p>
  
  <ul>
  <li>must Contain 11 Digits</li>
  <li>must Begin with '01'</li>
  <li>the third digit must be either '2' or '1' or '0'</li>
  </ul>