title: how to read the key names from a json response as case insensitive
body: <p>Below is my json format code:</p>
  
  <pre><code>{
      "topic": "Employee",
      "message": {
          "Id": "IND01",
          "data": {
              "salary": 50000
          }
      }
  }
  </code></pre>
  
  <p>The key names such as <code>topic</code>, <code>message</code>, <code>Id</code> and <code>data</code> to be read as case-insensitive. How can I get the keys from this json response body ?</p>