如何打印 Vue.js 的组件 ID

Question

there are a link of official document :

https://v2.vuejs.org/v2/guide/list.html#v-for-with-a-Component

Here's a complete example of a simple todo list:

 Vue.component('todo-item', { template: '\ <li>\ {{ title }}\ <button v-on:click="$emit(\'remove\')">X</button>\ </li>\ ', props: ['title'] }) new Vue({ el: '#todo-list-example', data: { newTodoText: '', todos: [ { id: 1, title: 'Do the dishes', }, { id: 2, title: 'Take out the trash', }, { id: 3, title: 'Mow the lawn' } ], nextTodoId: 4 }, methods: { addNewTodo: function () { this.todos.push({ id: this.nextTodoId++, title: this.newTodoText }) this.newTodoText = '' } } })

 <div id="todo-list-example"> <input v-model="newTodoText" v-on:keyup.enter="addNewTodo" placeholder="Add a todo" > <ul> <li is="todo-item" v-for="(todo, index) in todos" v-bind:key="todo.id" v-bind:title="todo.title" v-on:remove="todos.splice(index, 1)" ></li> </ul> </div>

results: enter image description here

---

i try to print todo.id . for example:

 Vue.component('todo-item', { template: '\ <li>\ {{ id }}-{{ title }}\ <button v-on:click="$emit(\'remove\')">X</button>\ </li>\ ', props: ['id','title'] })

but the result is the same enter image description here so, how should i print the todo.id?

Answer 1

Firstly, you need to actually provide the id to the <li is="todo-item" ... > s, which isn't being done. You need to add v-bind:id="todo.id" .

That being said, if you're trying to print it from any of the Vue instance lifecycle hooks , then it's as easy as console.log(this.id) . For example:

Vue.component('todo-item', {
  ...
  mounted(){
    console.log(this.id)
  }
}

PS don't use jQuery! Using jQuery with Vue is a code-smell. Here's a pretty informational rant by Gitlab on why that is (plus more).