<template>  <el-select    v-model="value"    placeholder="請選擇"    filterable    multiple    v-el-select-loadmore="loadmore"  >    <el-option      v-for="item in options"      :key="item.id"      :label="item.label"      :value="item.id">    </el-option>  </el-select></template> export default {  directives: {    'el-select-loadmore': {      bind(el, binding) {        // 獲取element-ui定義好的scroll盒子        const SELECTWRAP_DOM = el.querySelector('.el-select-dropdown .el-select-dropdown__wrap');        SELECTWRAP_DOM.addEventListener('scroll', function () {          /**          * scrollHeight 獲取元素內容高度(只讀)          * scrollTop 獲取或者設置元素的偏移值,常用于, 計算滾動條的位置, 當一個元素的容器沒有產生垂直方向的滾動條, 那它的scrollTop的值默認為0.          * clientHeight 讀取元素的可見高度(只讀)          * 如果元素滾動到底, 下面等式返回true, 沒有則返回false:          * ele.scrollHeight - ele.scrollTop === ele.clientHeight;          */          const condition = this.scrollHeight - this.scrollTop <= this.clientHeight;          if (condition) {            binding.value();          }        });      }    }  },  data() {    return {      value: '',      options: [],      formData: {        pageIndex: 1,        pageSize: 20,      }    };  },  mounted() {    this.getList(this.formData);  },  methods: {    loadmore() {      this.formData.pageIndex++;      this.getList(this.formData);    },    getList(formData) {      // 這里是接口請求數據, 帶分頁條件      const _res = [1, 2, 3]; // 請求得到的數據      this.options = [...this.options, ..._res];    }  }};