title: How to print json property name?
body: <p>I have a json in the following format:</p>
  
  <pre><code>{
   "nm_questionario":{"isEmpty":"MSGE1 - Nome do Question&amp;aacute;rio"},
   "ds_questionario":{"isEmpty":"MSGE1 - Descri&amp;ccedil;&amp;atilde;o do Question&amp;aacute;rio"},
   "dt_inicio_vigencia":{"isEmpty":"MSGE1 - Data de Vig&amp;ecirc;ncia"}
  }
  </code></pre>
  
  <p>how can I print the names of the properties using javascript? I want to retrieve the names <code>nm_questionario</code>, <code>dt_inicio_vigencia</code> and <code>ds_questionario</code>. Tried many things already but to no avail.</p>