title: How to check if the key exist in json array?
body: <p>I have a json object, the structure of which is given below. I try to find if the key (for eg: <code>1</code> &amp; <code>2</code>) exist or not by myArray.includes(<code>'1'</code>) but it doesn't work. Is looping through the array the only way to check if attribute exist or not?</p>
  
  <pre><code>[{"1": [{}]},{"2": [{}]}]
  </code></pre>