title: Parsing JSON File from XMLHttpRequest
body: <p>I would like to use data within a JSON file which I get by using the XMLHttpRequest. I already checked that I recieve the file.</p>
  
  <pre><code>var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
      if (this.readyState == 4 &amp;&amp; this.status == 200) {
          document.getElementById("demo").innerHTML = this.responseText;
      }
  };
  var obj = xhttp.open("GET", "../data/data.json", true);
  xhttp.send();
  var obj1 = JSON.parse(obj);
  a0 = obj1.a0;
  </code></pre>
  
  <p>This is my JSON file.</p>
  
  <pre><code>{"a0":2, "a1": -2.356, "a2": 4.712}
  </code></pre>
  
  <p>I can't find the mistake I am doing here. Can you help?</p>