element UI select组件全选

　<el-select class="fr" v-model="searchJobType" style=" 185px; margin-right:8px;" size="mini" type="text" multiple collapse-tags @change="changeSelect" placeholder="请选择类型查询">
    <el-option v-for="(type,ind) in typeList" :key=ind :label="type.label" :value="type.value"></el-option>
  </el-select>

var Main = {
    data() {
      return {
        searchJobType: ['ALL_SELECT','00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '10'],
        oldSearchJobType: [['ALL_SELECT','00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '10']],
        typeList: [
          {value: 'ALL_SELECT', label: '全部'},
          {value: '00', label: 'label0'},
          {value: '01', label: 'label1'},
          {value: '02', label: 'label2'},
          {value: '03', label: 'label3'},
          {value: '04', label: 'label4'},
          {value: '05', label: 'label5'},
          {value: '06', label: 'label6'},
          {value: '07', label: 'label7'},
          {value: '08', label: 'label8'},
          {value: '09', label: 'label9'},
          {value: '10', label: 'label10'},
        ]
      }
    },
    methods:{
        changeSelect(val) {
        const allValues = [];
        // 保留所有值
        for (const item of this.typeList) {
          allValues.push(item.value)
        }
        // 用来储存上一次的值，可以进行对比
        const oldVal = this.oldSearchJobType.length === 1 ? this.oldSearchJobType[0] : [];
        // 若是全部选择
        if (val.includes('ALL_SELECT')) this.searchJobType = allValues;
        // 取消全部选中 上次有 当前没有 表示取消全选
        if (oldVal.includes('ALL_SELECT') && !val.includes('ALL_SELECT')) this.searchJobType = [];
        // 点击非全部选中 需要排除全部选中 以及 当前点击的选项
        // 新老数据都有全部选中
        if (oldVal.includes('ALL_SELECT') && val.includes('ALL_SELECT')) {
          const index = val.indexOf('ALL_SELECT');
          val.splice(index, 1); // 排除全选选项
          this.searchJobType = val
        }
        // 全选未选 但是其他选项全部选上 则全选选上 上次和当前 都没有全选
        if (!oldVal.includes('ALL_SELECT') && !val.includes('ALL_SELECT')) {
          if (val.length === allValues.length - 1) this.searchJobType = ['ALL_SELECT'].concat(val)
        }
        // 储存当前最后的结果 作为下次的老数据
        this.oldSearchJobType[0] = this.searchJobType;
      },
    }
  }
var Ctor = Vue.extend(Main)
new Ctor().$mount('#app')