How to remove an item from an array in Vue.js

Question

I am new to vue.js (2) and I am currently working on a simple event app. I've managed to add events but now I would like to delete events based on clicking on a button.

HTML

    <div class="list-group">

        <div class="list-group-item" v-for="event in events">
            <h4 class="list-group-item-heading">
                {{ event.name }}
            </h4>

            <h5>
                {{ event.date }}
            </h5>

            <p class="list-group-item-text" v-if="event.description">{{ event.description }}</p>

            <button class="btn btn-xs btn-danger" @click="deleteEvent(event)">Delete</button>
        </div>

    </div>
</div>

JS(Vue)

new Vue ({
    el: '#app',

    data: {
        events: [
            {
                id: 1,
                name: 'Event 1',
                description: 'Just some lorem ipsum',
                date: '2015-09-10'
            },
            {
                id: 2,
                name: 'Event 2',
                description: 'Just another lorem ipsum',
                date: '2015-10-02'
            }
        ],

        event: { name: '', description: '', date: '' }
    },

    ready: function() {

    },

    methods: {

        deleteEvent: function(event) {
                this.events.splice(this.event);
        },

        // Adds an event to the existing events array
        addEvent: function() {
            if(this.event.name) {
                this.events.push(this.event);
                this.event = { name: '', description: '', date: '' };
            }
        }

    } // end of methods

});

I've tried to pass the event to the function and than delete that one with the slice function, I thought it was that code for deleting some data from the array. What is the best en cleanest way to delete data from the array with a simpleb button and onclick event?

Answer 1

Don't forget to bind key attribute otherwise always last item will be deleted

Correct way to delete selected item from array:

Template

<div v-for="(item, index) in items" :key="item.id">
  <input v-model="item.value">
   <button @click="deleteItem(index)">
  delete
</button>

script

deleteItem(index) {
  this.items.splice(index, 1); \\OR   this.$delete(this.items,index)
 \\both will do the same
}

Answer 2

You can also use .$delete:

remove (index) {
 this.$delete(this.finds, index)
}

sources:

• https://vuejs.org/v2/api/#Vue-delete
• https://medium.com/vuejs-tips/tip-3-deleting-array-index-in-vue-js-8cc31d7214bf

Answer 3

You're using splice in a wrong way.

The overloads are:

array.splice(start)

array.splice(start, deleteCount)

array.splice(start, deleteCount, item1, item2, ...)

Start means the index that you want to start, not the element you want to remove. And you should pass the second parameter deleteCount as 1, which means: "I want to delete 1 element starting at the index {start}".

So you better go with:

deleteEvent: function(event) {
  this.events.splice(this.events.indexOf(event), 1);
}

Also, you're using a parameter, so you access it directly, not with this.event.

But in this way you will look up unnecessary for the indexOf in every delete, for solving this you can define the index variable at your v-for, and then pass it instead of the event object.

That is:

v-for="(event, index) in events"
...

<button ... @click="deleteEvent(index)"

And:

deleteEvent: function(index) {
  this.events.splice(index, 1);
}

Answer 4

It is even funnier when you are doing it with inputs, because they should be bound. If you are interested how to do it in vue2 and having options to insert and delete it:

please have a look an js fiddle

new Vue({
  el: '#app',
  data: {
    finds: [] 
  },
  methods: {
    addFind: function () {
      this.finds.push({ value: 'def' });
    },
    deleteFind: function (index) {
      console.log(index);
      console.log(this.finds);
      this.finds.splice(index, 1);
    }
  }
});

<script src="https://unpkg.com/vue@2.5.3/dist/vue.js"></script>
<div id="app">
  <h1>Finds</h1>
  <div v-for="(find, index) in finds">
    <input v-model="find.value">
    <button @click="deleteFind(index)">
      delete
    </button>
  </div>
  
  <button @click="addFind">
    New Find
  </button>
  
  <pre>{{ $data }}</pre>
</div>