Vue3的多种组件通信方式

 父组件向子组件传递数据 (Props)

父组件

<template><child :name="name"></child>
</template><script setup>
import { ref } from 'vue'
import Child from './Child.vue'const name = ref('小明')
</script>

子组件

<template><div>{{ props.name }}</div>
</template><script setup>
import { defineProps } from 'vue'const props = defineProps({name: {type: String,default: '',},
})
</script>

子组件向父组件传递数据 (Emit)

子组件

<template><button @click="handleClick">点击我</button>
</template><script setup>
import { ref, defineEmits } from 'vue'const message = ref('来自子组件的问候')
const emits = defineEmits(['greet'])const handleClick = () => {emits('greet', message.value)
}
</script>

父组件

<template><child @greet="handleGreet"></child>
</template><script setup>
import { ref } from 'vue'
import Child from './Child.vue'const handleGreet = (message) => {console.log(message) // 输出: "来自子组件的问候"
}
</script>

兄弟组件通信 (Mitt)

npm install --save mitt

mainjs全局配置

import { createApp } from 'vue'
import mitt from 'mitt'
import App from './App.vue'const app = createApp(App)
app.config.globalProperties.$bus = mitt()app.mount('#app')

发送事件组件

<script setup>
import { getCurrentInstance } from 'vue'const { proxy } = getCurrentInstance()
const sendMessage = () => {proxy.$bus.emit('myEvent', '你好,兄弟')
}
</script>

接受事件组件

<script setup>
import { onMounted, getCurrentInstance } from 'vue'const { proxy } = getCurrentInstance()onMounted(() => {proxy.$bus.on('myEvent', (message) => {console.log(message) // 输出: "你好,兄弟"})
})
</script>

透传 Attributes ($attrs)

父组件

<template><child name="小明" age="18" hobby="篮球"></child>
</template>

子组件

<script setup>
import { useAttrs } from 'vue'const attrs = useAttrs()
console.log(attrs) // { age: "18", hobby: "篮球" }
</script>

模板引用 (Refs)

父组件

<template><child ref="childRef"></child><button @click="callChildMethod">调用子组件方法</button>
</template><script setup>
import { ref } from 'vue'
import Child from './Child.vue'const childRef = ref(null)const callChildMethod = () => {childRef.value.someMethod()
}
</script>

子组件

<script setup>
import { defineExpose } from 'vue'const someMethod = () => {console.log('子组件方法被调用了')
}defineExpose({someMethod,
})
</script>

双向绑定 (v-model)

父组件

<template><child v-model:name="name"></child>
</template><script setup>
import { ref } from 'vue'
import Child from './Child.vue'const name = ref('小明')
</script>

子组件

<template><input :value="name" @input="updateName" />
</template><script setup>
import { defineProps, defineEmits } from 'vue'const props = defineProps(['name'])
const emit = defineEmits(['update:name'])const updateName = (e) => {emit('update:name', e.target.value)
}
</script>

依赖注入 (Provide/Inject)

爷组件

<script setup>
import { provide, ref } from 'vue'const themeColor = ref('blue')
provide('theme', themeColor)
</script>

子孙组件

<script setup>
import { inject } from 'vue'const theme = inject('theme')
console.log(theme.value) // 'blue'
</script>

路由传参

通过query

import { useRouter } from 'vue-router'const router = useRouter()
router.push({ path: '/user', query: { id: 123 } })// 在目标组件中
import { useRoute } from 'vue-router'const route = useRoute()
console.log(route.query.id) // 123

Vuex 状态管理

// store/index.js
import { createStore } from 'vuex'export default createStore({state: {count: 0,},mutations: {increment(state) {state.count++},},
})// 在组件中使用
import { useStore } from 'vuex'const store = useStore()
console.log(store.state.count)
store.commit('increment')

Pinia 状态管理

// stores/counter.js
import { defineStore } from 'pinia'export const useCounterStore = defineStore('counter', {state: () => ({ count: 0 }),actions: {increment() {this.count++},},
})// 在组件中使用
import { useCounterStore } from '@/stores/counter'const counter = useCounterStore()
console.log(counter.count)
counter.increment()

浏览器存储

localStorage 和 sessionStorage 可以用于在不同页面或组件之间共享数据。

// 存储数据
localStorage.setItem('user', JSON.stringify({ name: '小明', age: 18 }))// 读取数据
const user = JSON.parse(localStorage.getItem('user'))

Window 对象

// 设置全局数据
window.globalData = { message: '全局消息' }// 在任何地方使用
console.log(window.globalData.message)

 全局属性

Vue 3 提供了 app.config.globalProperties 来替代 Vue 2 中的 Vue.prototype,用于添加全局可用的属性。

// main.js
const app = createApp(App)
app.config.globalProperties.$http = axios// 在组件中使用
import { getCurrentInstance } from 'vue'const { proxy } = getCurrentInstance()
proxy.$http.get('/api/data')