I give you below very simple example so you can understand how to get array length or object length in Vue js code.

Example:

<!DOCTYPE html>
<html>
<head>
    <title>Vue JS Get Array Length Or Object Length Example - rathorji.in</title>
    <script src="https://cdn.jsdelivr.net/npm/vue"></script>
</head>
<body>
   
<div id="app">
   
  <ul id="exampleApp">
    <li v-if="myArray.length">Object Length = {{ myArray.length }}</li>
    <li v-for="value in myArray">
      {{ value.category }}
    </li>
  </ul>
  
</div>
  
<script type="text/javascript">
  
    var app = new Vue({
      el: '#app',
      data: {
        myArray: [
          { category: 'Laravel' },
          { category: 'PHP' },
          { category: 'Codeigniter' }
        ]
      }
    })
  
</script>
  
</body>
</html>

I hope this will help you...