Vue js valueOf Array Method

<html>
  <head>
    <script type="importmap">
      {
        "imports": {
          "vue": "https://unpkg.com/vue@3/dist/vue.esm-browser.js"
        }
      }
    </script>
    <body>
     <div id="app">
      <h2>Vue js array.valueOf() function from object</h2>
      <p>Get all property of array of object</p>
      <button @click='myFunction' class='btn btn-primary'>click me </button>
      <p></p>
      <p v-for="result in results">{{result}}</p>
     </div>
     <script type="module">
      import { createApp } from 'vue'
      createApp({
      data()
      { 
        return{ 
         countries:[ 
                  {
                   'countryName':'Australia',
                   'capitalName':'Canberra'
                  },
                  {
                    'countryName':'England',
                    'capitalName':'London'
                   },
                   {
                     'countryName':'India',
                     'capitalName':'New Delhi'
                   },
                ],
         results : ''
        } 
     }, 
     methods:{ 
         myFunction(){ 
            this.results = this.countries.valueOf()
           },
          }
      }).mount('#app')
  </script>

</body>
  </head>
</html>