title: Regular Expression for Alphabetic Letter with accent
body: <p>I need a validation a texbox in c# and asp.net using Regular Expression.</p>
  
  <p>I need allow:</p>
  
  <ul>
  <li>alphabetic letters UPPERCASE and lowercase or any ComBINAtion</li>
  <li>accented letters like: èèéàù ...</li>
  <li>numbers</li>
  <li>only one white space " "</li>
  </ul>
  
  <p>I need dot NOT allow:</p>
  
  <ul>
  <li>any special characters like: |!"£$%&amp;/()&lt;> ...</li>
  </ul>
  
  <p>Any ideas? Thanks for your help</p>