title: React: How to access array in an object?
body: <p>Bit of a rookie question &amp; late in the day, but how do I access an array in an object? I am getting <code>undefined</code> &amp; <code>TypeError: Cannot read property 'length' of undefined</code>. I can get the object data (Id, ElemId, etc) fine. </p>
  
  <pre><code>...
  this.state = {
     yfinder: [],
     ...
  }
  
  ...then api call...
  this.setState({
    finder: res.Finder,
    ...
  })
  </code></pre>
  
  <p><strong>JSON:</strong></p>
  
  <pre><code>"Finder": {
      "Id": "23216245567u4",
      "ElemId": "finder",
      "Title": "Your Finder",
      "Description": "This is a description",
      "ResultsTitle": "What program or service are you looking for?",
      "CategoryTitle": "Great! Select a category to continue..",
      "Results": [
         {
           ...
         }
         {
           ...
         }
      ]
  }
  let finder = this.state.finder;
  console.log(finder.Results);
  
  for (var i = 0; i &lt; finder.Results.length; i++) {
    console.log(finder.Results[i]); 
  }
  </code></pre>