title: Validate array of objects in express validator
body: <p>I am using express validator to validate my fields. But now i have array of 2 or 3 objects, which contains the "userId" and "Hours" fields like below.</p>
  
  <pre><code>[
    {
      user_id:1,
      hours:8
    },
    {
      user_id:2,
      hours:7
    }
  ]
  </code></pre>
  
  <p>Now i need to validate, if any of object property like <strong>hours or user_id</strong> is empty or not.if empty throw it's error.</p>