Vue2 组件通信方式

props/emit

props

作用：父组件通过 props 向子组件传递数据

parent.vue

<template>
    <div>
        <Son :msg="msg" :pfn="pFn"></Son>
    </div>
</template>

<script>
import Son from './son'
export default {
    name: 'Parent',
    data() {
        return {
            msg:'a message'
        }
    },
    methods: {
        pFn(){
            console.log("这是pFn");
        }
    },
    components:{
        Son
    }
}
</script>

<style></style>

son.vue

<template>
    <div>
        <h3>p的msg：{{ msg }}</h3>
        <el-button type="primary" size="default" @click="pfn">点击使用p的方法</el-button>
    </div>
</template>

<script>
export default {
    name: 'Son',
    props:['pfn','msg']
}
</script>

<style></style>

效果

emit

作用：子组件通过 $emit 和父组件通信

parent.vue

<template>
    <div>
        <Son :msg="msg"  @onSendData="onSendData"></Son>
    </div>
</template>

<script>
import Son from './son'
export default {
    name: 'Parent',
    data() {
        return {
            msg:'a message'
        }
    },
    methods: {
    },
    components:{
        Son
    },
    methods: {
        onSendData(val){
            console.log(val);
        }
    },
}
</script>

<style></style>

son.vue

<template>
    <div>
        <h3>p的msg：{{ msg }}</h3>
      <el-button type="primary" size="default" @click="sendData">点击向p发送数据</el-button> 
    </div>
</template>

<script>
export default {
    name: 'Son',
    props:['msg'],
    created() {
        console.log(this);
    },
    methods: {
        sendData(){
            this.$emit("onSendData",'data from son')
        }
    },
}
</script>

<style></style>

效果

ref / $refs

作用:这个属性用在子组件上，它的用用就指向了子组件的实例，可以通过实例来访问组件的数据和方法

parent.vue

<template>
    <div>
        <Son ref="Son"></Son>
    </div>
</template>

<script>
import Son from './son.vue';
export default {
    name: 'Parent',
    components:{
        Son,
    },
    mounted() {
        console.log("this.$refs.Son",this.$refs.Son.msg);
        this.$refs.Son.sayHi();
    },
   
}
</script>

<style></style>

son.vue

<template>
    <div>
        <h3>p的msg：{{ msg }}</h3>
    </div>
</template>

<script>
export default {
    name: 'Son',
    data() {
        return {
            msg:"a message from son"
        }
    },
    methods: {
        sayHi(){
            console.log("hello");
        }
    },
}
</script>

<style></style>