title: How do I get http headers in React.js
body: <p>I've made a request to a React page, and I need to get the headers from the request.</p>
  
  <p>I call the page via the URL:</p>
  
  <p><a href="http://localhost/dashboard" rel="noreferrer">http://localhost/dashboard</a></p>
  
  <p>and I set headers, for example authcode=1234.</p>
  
  <p>I then load the page with this route:</p>
  
  <pre><code>&lt;Route path="dashboard" name="dashboard" component={Dashboard} onEnter={requireAuth}&gt;&lt;/Route&gt;
  </code></pre>
  
  <p>is there something like this.props.header, I can call in the page constructor?</p>