title: Reverse the order of Hex digits
body: <p>I need to take an integer value and convert it so that when it is represented in hexadecimal, the digits are reversed.  For instance:</p>
  
  <pre><code>Dim a As Integer = &amp;H4321
  Dim a_changedorder As Integer = ReverseHexDigits(a)
  Console.Writeline(a_changedorder.ToString("X4")) ' Should output 1234
  </code></pre>
  
  <p>How can I implement a <code>ReverseHexDigits</code> method that works like that?</p>
  
  <p>As a second example, <code>&amp;H4F2A</code> should become <code>&amp;HA2F4</code>.</p>