解决element-ui el-select数据过大方案

一、背景

项目中需要用到el-select选择医院，全国医院数据量非常大，通过API读取数据页面直接卡死。

二、解决方案

1、组件：el-select + vue虚拟滚动（vue-virtual-scroll-list）

2、安装：npm install vue-virtual-scroll-list --save

3、参考：

　　　　NPM地址：https://www.npmjs.com/package/vue-virtual-scroll-list

　　　　官网地址：https://tangbc.github.io/vue-virtual-scroll-list/#/

三：参考代码

###create.vue

<template>

  <div>
    <el-form ref="dataForm" :model="form" :rules="rules" label-width="0px">
      <el-descriptions :column="3" border>

        <el-descriptions-item labelStyle="width: 13%" contentStyle="width: 20%">
            <template slot="label"><span class="red">*</span> 医院</template>
            <el-form-item label="" prop="hospital_id">
              <el-select
                  @change="changeValue"
                  remote
                  :remote-method="getListHospital"
                  :loading="loading"
                  v-model="form.hospital_id"
                  :placeholder="'请输入医院'"
                  size="small"
                  filterable
                  clearable>
                <virtual-list
                    style="height: 150px; overflow-y: auto;"
                    :data-key="'id'"
                    :data-sources="hospitalData"
                    :data-component="itemComponent"
                />
              </el-select>
            </el-form-item>
          </el-descriptions-item>
      </el-descriptions>
    </el-form>
  </div>
</template>

<script>

import {allHospital, listHospital} from "@/api/system/hospital";
import Item from "./item";
import VirtualList from 'vue-virtual-scroll-list'

export default {
  props: ["rowData", "dialogStatus"],
  components: {
    VirtualList,
  },
  data() {
    return {
      itemComponent: Item,
      hospitalData: [],
      loading: false,
    };
  },
  created() {
    if (this.dialogStatus === "update" || this.dialogStatus === "detail") {
      this.form = {...this.rowData};
      this.getAllHospital();
    }
  },

  methods: {
    
    changeValue(id) {
      if (id) {
        let item = this.hospitalData.find(item => item.id === id);
        this.form.hospital_name = item.hospital
      }
    },
    /**
     * 获取医院列表
     */
    getAllHospital() {
      if (this.form.hospital_id !== '') {
        let param = {
          id: this.form.hospital_id,
          field:"id,hospital"
        };
        allHospital(param).then((res) => {
          if (res.code === 200) {
            this.hospitalData = res.data;
          }
        });
      }
    },
    getListHospital(query) {
      if (query !== '') {
        this.loading = true;
        setTimeout(() => {
          this.loading = false;
          let param = {
            hospital: query,
            pageSize: 100,
            field:"id,hospital"
          };
          listHospital(param).then((res) => {
            if (res.code === 200) {
              this.hospitalData = res.data.data;
            }
          });
        }, 200);
      }
    },

  },
};
</script>



###item.vue

<template>
  <el-option :label="source.hospital" :value="source.id"></el-option>
</template>

<script>
export default {
  name: 'item-component',
  props: {
    index: { // index of current item
      type: Number
    },
    source: { // here is: {uid: 'unique_1', text: 'abc'}
      type: Object,
      default() {
        return {}
      }
    }
  }
}
</script>

四：解决样式

1、支持el-select一切属性，利用select远程搜索，解决大数据查找问题