Vue组件通信：使用v-on指令进行事件传递

<!-- 父组件 -->
<template>
  <div>
    <p>父组件</p>
    <child-component v-on:child-event="handleChildEvent"></child-component>
  </div>
</template>

<script>
import ChildComponent from './ChildComponent.vue';

export default {
  components: {
    ChildComponent,
  },
  methods: {
    handleChildEvent() {
      console.log('子组件事件触发');
    },
  },
};
</script>

<!-- 子组件 -->
<template>
  <div>
    <p>子组件</p>
    <button v-on:click="$emit('child-event')">触发子组件事件</button>
  </div>
</template>

<script>
export default {
};
</script>

<!-- 组件A -->
<template>
  <div>
    <p>组件A</p>
    <button v-on:click="handleButtonClick">触发事件</button>
  </div>
</template>

<script>
export default {
  methods: {
    handleButtonClick() {
      this.$emit('a-event');
    },
  },
};
</script>

<!-- 组件B -->
<template>
  <div>
    <p>组件B</p>
    <p>{{ message }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      message: '',
    };
  },
  mounted() {
    this.$root.$on('a-event', this.handleAEvent);
  },
  methods: {
    handleAEvent() {
      this.message = '收到组件A的事件';
    },
  },
};
</script>