[
 {
  "value": "110000",
  "label": "北京市",
  "children": [
   {
    "value": "110000",
    "label": "北京市",
    "children": [
     {
      "value": "110101",
      "label": "东城区"
     },
     {
      "value": "110102",
      "label": "西城区"
     },
     {
      "value": "110105",
      "label": "朝阳区"
     },
     {
      "value": "110106",
      "label": "丰台区"
     },
     {
      "value": "110107",
      "label": "石景山区"
     },
     {
      "value": "110108",
      "label": "海淀区"
     },
     {
      "value": "110109",
      "label": "门头沟区"
     },
     {
      "value": "110111",
      "label": "房山区"
     },
     {
      "value": "110112",
      "label": "通州区"
     },
     {
      "value": "110113",
      "label": "顺义区"
     },
     {
      "value": "110114",
      "label": "昌平区"
     },
     {
      "value": "110115",
      "label": "大兴区"
     },
     {
      "value": "110116",
      "label": "怀柔区"
     },
     {
      "value": "110117",
      "label": "平谷区"
     },
     {
      "value": "110118",
      "label": "密云区"
     },
     {
      "value": "110119",
      "label": "延庆区"
     }
    ]
   }
  ]
 },
 {
  "value": "120000",
  "label": "天津市",
  "children": [
   {
    "value": "120000",
    "label": "天津市",
    "children": [
     {
      "value": "120101",
      "label": "和平区"
     },
     ......

<template>
 <div class="linkage">
  <div>
   <el-select v-model="selectProvince" filterable size="small" @change="selectProvinceFun($event)" placeholder="请选择省份">
    <el-option value="" label="请选择省份"></el-option>
    <el-option :value="item" :label="item.label" v-for="(item, index) in city" :key="index"></el-option>
   </el-select>
  </div>
  <div>
   <el-select v-model="selectCity" filterable size="small" @change="selectCityFun($event)" placeholder="请选择城市">
    <el-option value="" label="请选择城市"></el-option>
    <el-option :value="item" :label="item.label" v-for="(item, index) in cityList" :key="index"></el-option>
   </el-select>
  </div>
  <div>
   <el-select v-model="selectArea" filterable size="small" @change="selectAreaFun($event)" placeholder="请选择区县">
    <el-option value="" label="请选择区县"></el-option>
    <el-option :value="item" :label="item.label" v-for="(item, index) in areaList" :key="index"></el-option>
   </el-select>
  </div>
 </div>
</template>
<script>
import city from '@/assets/json/city.json'
export default {
 name: 'linkage',
 data () {
  return {
   // 整个省市县数据
   city: city,
   // 被选中的市数据
   cityList: [],
   // 被选中的县数据
   areaList: [],
   selectProvince: {},
   selectCity: {},
   selectArea: {}
  }
 },
 mounted () {
 },
 methods: {
  // 省份 市 县联动
  selectProvinceFun (event) {
   console.log(event)
   if (event) {
    this.cityList = event.children
   } else {
    this.cityList = []
   }
   this.areaList = []
   this.$emit('getLawyerListInfo', [event.label, 'province'])
  },
  selectCityFun (event) {
   console.log(event)
   if (event) {
    this.areaList = event.children
   } else {
    this.areaList = []
   }
   this.$emit('getLawyerListInfo', [event.label, 'city'])
  },
  selectAreaFun (event) {
   console.log(event)
   this.$emit('getLawyerListInfo', [event.label, 'area'])
  }
 }
}
</script>
<style lang="scss" scoped>
 .linkage {
  display: flex;
  div {
   margin-right: 5px;
  }
 }
</style>