title: IDataErrorInfo vs ValidationRule vs Exception
body: <p>Can anyone tell me which is a better approach for Validation in WPF. </p>
  
  <ol>
  <li>Implementing IDataErrorInfo</li>
  <li>Creating ValidationRule</li>
  <li>Throwing Exceptions</li>
  </ol>
  
  <p>in terms of performance, memory leaks, code maintainability and re-use.</p>