title: How to get "Data" field from xhr.responseText?
body: <p>I have <code>XMLHttpRequest()</code> function given below</p>
  
  <pre><code>var searchFriendRequests = function (userid) {
      var xhr = new XMLHttpRequest();
      xhr.open('GET', 'http://localhost:6344/api/Registeration/searchFriendrequests?userid=' + userid, false);
      xhr.setRequestHeader("Content-Type", "text/xml");
      xhr.onreadystatechange = function () {
          if (xhr.readyState == 4) {
              if (xhr.status == 200) {
                  var data = xhr.responseText;
              }
          }
      };
      xhr.send(null);
  }
  </code></pre>
  
  <p>where <code>xhr.responseText</code> returns value as </p>
  
  <pre><code>{
      "$id": "1",
      "ContentEncoding": null,
      "ContentType": null,
      "Data": [
          {
              "$id": "2",
              "email": "anu@gmail.com"
          },
          {
              "$id": "3",
              "email": "anu@gmail.com"
          }
      ],
      "JsonRequestBehavior": 1,
      "MaxJsonLength": null,
      "RecursionLimit": null
  }
  </code></pre>
  
  <p>How can I get the <code>Data</code> field from the <code>responseText</code>?</p>