Mega Code Archive
Use a validator along with a data binding to validate
<![CDATA[
<?xml version="1.0"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Model id="userInfo">
<phoneInfo>
<phoneNum>{phoneInput.text}</phoneNum>
</phoneInfo>
</mx:Model>
<mx:PhoneNumberValidator id="pnV" source="{phoneInput}" property="text" />
<mx:TextInput id="phoneInput" />
<mx:TextInput id="zipCodeInput" />
</mx:Application>
]]>