title: How Get some specific value from Rails string?
body: <p>I want to get some specific value from string of Rails like below these are two string.</p>
  
  <pre><code> 1. "http://localhost:3000/admin/shops/assign_shoes?id=50&amp;page=1"
  
   2. "http://localhost:3000/admin/shops/assign_shoes?id=50"
  </code></pre>
  
  <p>I always need value of "id" which is "50". Don't matter how many parameters are in string </p>
  
  <p>as query string.</p>
  
  <p>Actually these strings are values of <strong>request.referer</strong></p>
  
  <p>Any efficient method?</p>
  
  <p>Thanks</p>