javascript - 组件无法从 Vue 实例 v-on :click 调用方法

Question

我对 Vuejs 很陌生，我只想从我的 Vue 实例中调用一个方法，但这似乎是一个问题，我不知道为什么。
Vue 实例:

var monster = new Vue({
    el: '#monsterlist',
    data: {
        monsters: undefined
    },
    created: async function (){
        this.monsters = await this.loadMonster()
    },
    methods: {
        loadMonster: async function () {
            //stuff
        },
        deleteMonster: async function(id){
            //stuff
        }
    }
})

成分:

Vue.component('monster', {
    template: '<div class="content overlayable"> <div class="overlay" v-if="monster.deleting"><div class="lds-ripple"><div></div><div></div></div></div> <div><h1>{{monster.name}}</h1> <div class="static"> <div class="des"><img v-if="monster.image != undefined && monster.image != ``" :src="monster.image"> <a v-else>No monster image</a></div> <button class="denyBtn" v-on:click="deleteMonster(monster._id)">Delete</button> </div></div> </div>',
    props: ['monster']
})

我想使用我的怪物的 id 调用 deleteMonster() 方法，并在组件中声明一个按钮。
这是我得到的错误:

vue@2:6 ReferenceError: deleteMonster is not defined
    at click (eval at Ya (vue@2:6), <anonymous>:3:451)
    at He (vue@2:6)
    at HTMLButtonElement.n (vue@2:6)
    at HTMLButtonElement.Yr.o._wrapper (vue@2:6)

Answer 1

您需要emit父组件的事件 monsterlist调用它的 deleteMonster传递自定义的函数 id如下:

const monster = Vue.component('monster', {
  template: '#monster',
  props: ['monster']
})

new Vue({
  el: '#monsterlist',
  components: { monster },
  data: {
    monsters: undefined
  },
  created: async function (){
    this.monsters = await this.loadMonster()
  },
  methods: {
    loadMonster: async function () {
      return [
        {_id:1},
        {_id:2},
      ];
    },
    deleteMonster: async function(id){
      console.log(id);
    }
  }
})

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>

<div id="monsterlist">
  <monster 
    v-for="(monster,index) in monsters"
    :key="index"
    :monster="monster"
    @delete="deleteMonster"
  />
</div>

<template id="monster">
  <div class="content overlayable"> 
    <div class="overlay" v-if="monster.deleting">
      <div class="lds-ripple">
        <div></div>
        <div></div>
      </div>
    </div> 
    <div>
      <h1>{{monster.name}}</h1> 
      <div class="static"> 
        <div class="des">
          <img v-if="monster.image != undefined && monster.image != ``" :src="monster.image"> 
          <a v-else>No monster image</a>
        </div> 
        <button 
          class="denyBtn" 
          v-on:click="$emit('delete',monster._id)"
        >Delete</button> 
      </div>
    </div> 
  </div>
</template>