title: How to get this kind of parameter in node.js express router?
body: <p>I have a router like this:</p>
  
  <pre><code>app.get('/blog/:id/delete', function (req, res) {
  
  })
  </code></pre>
  
  <p>how can I get the <code>:id</code> parameter?</p>
  
  <p>I have tried <code>req.query.id</code>  <code>req.param.id</code> ,but both failed</p>
  
  <p>How can I get the correct <code>id</code> value?</p>