V-model of custom component

vue Official website definition ：

Two way binding

<input :value="something" @input="something = $event.target.value">

Grammatical sugar

<input v-model="something">

therefore

<custom-input v-model="something"></custom-input>

In custom components, it is equivalent to

<custom-input :value="something" @input="something = $event.target.value">
</custom-input>

Example

Parent component ：

<template>
      <el-form ref="form">
        <el-form-item label=" department ：">
            <frame-select v-model="form.depidProp"></frame-select>
        </el-form-item>
      </el-form>
</template>
<script>
import frameSelect from './component/frameSelect.vue'
export default {
  components: { frameSelect },
  data() {
    return {
      form: {
        depidProp:''
      },
    }
  },
  methods: { }
}
</script>

Child components

<template>
    <el-select v-model="modelValue" @change="changeOrgList">
      <el-option v-for="item in orgLevelList" 
       :label="item.name" :value="item.name" :key="item.id">
      </el-option>
    </el-select>
</template>
<script>
export default {
  props: {
    //value name 
    modelValue: {
      type: [String,Number],
      default: ''
    },
  },
  data() {
    return {
      orgLevelList: [{id:1,name:' Organization Department '},{id:2,name:' The personnel department '},{id:3,name:' Technology Department '}]
    }
  },
  model: {
    prop: 'modelValue',//value name 
    event: 'changeOrgList',// The method that the child component needs to register to update the parent component value 
  },
  methods: {
    changeOrgList(val) {
      this.$emit('changeOrgList', val)
    }
  }
}
</script>