Vue3组件通信的方法大全

<template>
  <ChildComponent name="訾博" :age="18" />
</template>

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

<template>
  <p>大家好，我叫{{ name }}，今年{{ age }}岁。</p>
</template>

<script setup>
// 接收父组件传来的props
const props = defineProps({
  name: String,
  age: {
    type: Number,
    required: true,
    default: 10
  }
});
</script>

<template>
  <button @click="tellDad">告诉爸爸我长大了</button>
</template>

<script setup>
// 声明要触发的事件
const emit = defineEmits(['grow-up']);

function tellDad() {
  // 触发事件，并可以传递参数
  emit('grow-up', '我已经会自己写代码了！');
}
</script>

<template>
  <ChildComponent @grow-up="handleChildGrowUp" />
  <p>来自儿子的消息：{{ messageFromChild }}</p>
</template>

<script setup>
import { ref } from 'vue';
import ChildComponent from './ChildComponent.vue';

const messageFromChild = ref('');

function handleChildGrowUp(message) {
  messageFromChild.value = message;
}
</script>

<template>
  <input :value="modelValue" @input="emit('update:modelValue', $event.target.value)" />
</template>

<script setup>
defineProps(['modelValue']);
const emit = defineEmits(['update:modelValue']);
</script>

<template>
  <CustomInput v-model="searchText" />
  <p>你在搜索：{{ searchText }}</p>
</template>

<script setup>
import { ref } from 'vue';
import CustomInput from './CustomInput.vue';

const searchText = ref('');
</script>

<template>
  <p>我是一个深藏不露的组件</p>
</template>

<script setup>
import { ref } from 'vue';

const doPushUp = () => {
  console.log('正在做俯卧撑...');
};

// 把doPushUp方法暴露给父组件
defineExpose({
  doPushUp
});
</script>

<template>
  <ChildComponent ref="childRef" />
  <button @click="commandChild">命令儿子</button>
</template>

<script setup>
import { ref } from 'vue';
import ChildComponent from './ChildComponent.vue';

const childRef = ref(null);

function commandChild() {
  // 通过.value访问到子组件实例，并调用其暴露的方法
  childRef.value.doPushUp();
}
</script>

<template>
  <ParentComponent />
</template>

<script setup>
import { provide, ref } from 'vue';

const themeColor = ref('dark');
// 提供数据，'theme'是暗号
provide('theme', themeColor); 
</script>

<template>
  <div :style="{ color: theme }">我是孙子组件，我用的是祖传主题色。</div>
</template>

<script setup>
import { inject } from 'vue';

// 注入数据，'theme'是暗号
const theme = inject('theme');
</script>

import { defineStore } from 'pinia';

export const useUserStore = defineStore('user', {
  state: () => ({
    name: '訾博',
    isLoggedIn: false,
  }),
  actions: {
    login() {
      this.isLoggedIn = true;
    },
  },
});

<template>
  <p v-if="userStore.isLoggedIn">欢迎回来, {{ userStore.name }}!</p>
  <button @click="userStore.login()">登录</button>
</template>

<script setup>
import { useUserStore } from '@/stores/user';

const userStore = useUserStore();
</script>

import mitt from 'mitt';
const emitter = mitt();
export default emitter;

<script setup>
import emitter from '@/utils/emitter';

function sendMessage() {
  emitter.emit('some-event', '来自A组件的问候');
}
</script>

<script setup>
import emitter from '@/utils/emitter';
import { onMounted, onUnmounted } from 'vue';

onMounted(() => {
  emitter.on('some-event', (message) => {
    console.log(message); // "来自A组件的问候"
  });
});

// 记住，一定要在组件卸载时取消监听，否则会内存泄漏！
onUnmounted(() => {
  emitter.off('some-event');
});
</script>