title: Fail to construct a POST Request instance in JavaScript
body: <p>According to <a href="https://developer.mozilla.org/en-US/docs/Web/API/Request" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/API/Request</a>. Following snippet can construct a POST Request instance in JavaScript.</p>
  
  <pre><code>var myRequest = new Request('http://localhost/api', {method: 'POST', body: '{"foo":"bar"}'});
  
  var myURL = myRequest.url; // http://localhost/api
  var myMethod = myRequest.method; // POST
  var myCred = myRequest.credentials; // omit
  var bodyUsed = myRequest.bodyUsed; // true
  </code></pre>
  
  <p>But in my Chrome browser, I got an instance without body but actually I passed the option with body to <code>Request</code>.
  <a href="https://i.stack.imgur.com/QZtub.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QZtub.png" alt="enter image description here"></a></p>
  
  <p>So how can I construct a POST Request?</p>