title: In node.js express , the default router always jump to index.html static file
body: <p>My default router is :</p>
  
  <pre><code>app.get('/', function (req, res) {
      console.log("default");
      res.send("ok");
  });
  </code></pre>
  
  <p>If I don't have a <code>index.html</code> in my static directory, the <code>log</code> and <code>send</code> will output as will,</p>
  
  <p>but when I add <code>index.html</code>, the router will direct jump to the page, then I change the name <code>index</code> to another name, it doesn't jump again.</p>
  
  <p>Why this happen? How can I change this setting things?</p>