Passing data to components in vue.js

-------------Following is applicable only to Vue 1 --------------

Passing data can be done in multiple ways. The method depends on the type of use.

If you want to pass data from your html while you add a new component. That is done using props.

<my-component prop-name="value"></my-component>

This prop value will be available to your component only if you add the prop name prop-name to your props attribute.

When data is passed from a component to another component because of some dynamic or static event. That is done by using event dispatchers and broadcasters. So for example if you have a component structure like this:

<my-parent>
    <my-child-A></my-child-A>
    <my-child-B></my-child-B>
</my-parent>

And you want to send data from <my-child-A> to <my-child-B> then in <my-child-A> you will have to dispatch an event:

this.$dispatch('event_name', data);

This event will travel all the way up the parent chain. And from whichever parent you have a branch toward <my-child-B> you broadcast the event along with the data. So in the parent:

events:{
    'event_name' : function(data){
        this.$broadcast('event_name', data);
    },

Now this broadcast will travel down the child chain. And at whichever child you want to grab the event, in our case <my-child-B> we will add another event:

events: {
    'event_name' : function(data){
        // Your code. 
    },
},

The third way to pass data is through parameters in v-links. This method is used when components chains are completely destroyed or in cases when the URI changes. And i can see you already understand them.

Decide what type of data communication you want, and choose appropriately.

The best way to send data from a parent component to a child is using props.

Passing data from parent to child via props

• Declare props (array or object) in the child
• Pass it to the child via <child :name="variableOnParent">

See demo below:

Vue.component('child-comp', {
  props: ['message'], // declare the props
  template: '<p>At child-comp, using props in the template: {{ message }}</p>',
  mounted: function () {
    console.log('The props are also available in JS:', this.message);
  }
})

new Vue({
  el: '#app',
  data: {
    variableAtParent: 'DATA FROM PARENT!'
  }
})

<script src="https://unpkg.com/[email protected]/dist/vue.min.js"></script>

<div id="app">
  <p>At Parent: {{ variableAtParent }}<br>And is reactive (edit it) <input v-model="variableAtParent"></p>
  <child-comp :message="variableAtParent"></child-comp>
</div>