vue.jsvuejs2vue-componentvuejs3

How to re-mount a component in VueJS?


I have a component which is mounted as part of the DOM rendering. The skeleton of the application is

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>title</title>
  </head>
  <body>
    <div id="app">
      <my-component></my-component>
      <button>press this button to reload the component</button>
    </div>
  </body>
</html>

<my-component> is functional (it displays a few form inputs) and $emit data to the parent.

Is there a way to re-mount it? The goal is to have a component content and setup as if it was just rendered for the first time (including a reset of the data() elements which hold its state).

There are some solutions to that but they all assume a rewrite of data(), which I would like to avoid.

My understanding is that a component is actuall HTML/CSS/JS code injected in the dom in the right place during the rendering so I fear that the concept of "re-mounting" it does not exist - I just wanted to make sure before going the data()-rewrite way.


Solution

  • The trick is to alter the key

    When the key changes, vue regards it as a new component, so it will unmount the "old" component, and mount a "new" component.

    See example, the created() hook will only run once, so if you see the value change, you're seeing a brand new object.

    example:

    Vue.component('my-component', {
      template: `<div>{{ rand }}</div>`,
      data() {
        return {
          remount: true
        }
      },
      created() {
        this.remount = !this.remount; // true▶false▶true▶false...
      }
    });
    
    new Vue({
      el: '#app',
      data: {
        componentKey:0
      }
    })
    <script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.8/vue.min.js"></script>
    
    <div id="app">
      <my-component :key="componentKey"></my-component>
      <button @click="componentKey=!componentKey">press this button to reload the component</button>
    </div>