title: how to mask first Five digit number on keyup using *
body: <p>For eg while i am typing my ssn number my first 5 dight must be masked to *</p>
  
  <pre><code>  123456789    =&gt;  *****6789
  </code></pre>
  
  <p>Note :<strong><em>on keyup</em></strong>  it should check no of digits and mask based on it.</p>
  
  <p>I came through this below example. It mask the entire nine digit.</p>
  
  <p><a href="https://codepen.io/anon/pen/VROrdo" rel="noreferrer">https://codepen.io/anon/pen/VROrdo</a></p>