title: Phone Number Formatting, OnBlur
body: <p>I have a .NET WinForms textbox for a phone number field.  After allowing free-form text, I'd like to format the text as a "more readable" phone number after the user leaves the textbox. (Outlook has this feature for phone fields when you create/edit a contact)</p>
  
  <ul>
  <li>1234567 becomes 123-4567</li>
  <li>1234567890 becomes (123) 456-7890</li>
  <li>(123)456.7890 becomes (123) 456-7890</li>
  <li>123.4567x123 becomes 123-4567 x123</li>
  <li>etc</li>
  </ul>