title: Json data- key values, Object.Keys error
body: <p>I am trying to parse out all keys from a json data.</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
      $(document).ready(function () {
          $.ajax({
              type: "POST",
              url: "History.aspx/GetFTEData",
              dataType: "json",
              contentType: "application/json; charset=utf-8",
              success: function (data) {
                  var returnedstring = data.d;
                  var colHeader = Object.keys(data[0]); &lt;---- error line
  
              }
          });
      });
  &lt;/script&gt;
  </code></pre>
  
  <p>However, <code>var colHeader = Object.keys(data[0]);</code> this doesn't work while running it with my IDE (VS2015) on my IE 11 or Firefox browser even though it works in the jsfiddle example:-</p>
  
  <p><a href="https://jsfiddle.net/qpu3cn5u/" rel="nofollow noreferrer">https://jsfiddle.net/qpu3cn5u/</a></p>
  
  <p>The error message:- 0x800a138f - JavaScript runtime error: Object.keys: argument is not an Object </p>
  
  <p>What alternatives do I have? such that I can only parse the keys out as column names for an html table that I am trying to populate with values.</p>
  
  <p>example of data:-</p>
  
  <pre><code>var data = `[{"Customer Name":"XXXX","1999":76.000,"2000":68.000,"2001":49.000,"2002":41.000,"2003":47.000,"2004":56.000,"2005":33.000,"2006":51.000,"2007":56.000,"2008":52.000,"2009":55.000,"2010":52.000,"2011":57.000,"2012":55.000,"2013":93.000,"2014":92.000,"2015":62.000,"2016":71.833},{"Customer Name":"YYYYY","1999":29.000,"2000":27.000,"2001":35.000,"2002":37.000,"2003":32.000,"2004":29.000,"2005":44.000,"2006":49.000,"2007":69.000,"2008":109.000,"2009":108.000,"2010":150.000,"2011":189.000,"2012":215.000,"2013":53.000,"2014":78.000,"2015":65.000,"2016":63.000},{"Customer Name":"ZZZZ","1999":0.000,"2000":0.000,"2001":0.000,"2002":0.000,"2003":0.000,"2004":0.000,"2005":0.000,"2006":0.000,"2007":0.000,"2008":0.000,"2009":0.000,"2010":0.000,"2011":0.000,"2012":28.000,"2013":36.000,"2014":59.000,"2015":90.000,"2016":94.000},{"Customer Name":"AAAAA","1999":0.000,"2000":0.000,"2001":0.000,"2002":0.000,"2003":0.000,"2004":0.000,"2005":0.000,"2006":0.000,"2007":0.000,"2008":0.000,"2009":0.000,"2010":0.000,"2011":0.000,"2012":18.000,"2013":18.000,"2014":18.000,"2015":19.000,"2016":18.000}]`
  </code></pre>