title: Restricting TextInput to email characters only
body: <p>Using Flex SDK 4.6, I'm trying to restrict a TextInput field to email characters only as follows:</p>
  
  <pre><code>textInput.restrict = "a-z A-z 0-9 \- _ @ .";
  </code></pre>
  
  <p>However when I run my application, the TextInput field accepts any character. I'm really not sure why this is not working and would appreciate any help.</p>