方法一：

<el-select v-model="value" placeholder="请选择" @change="change()">
   <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
</el-select>

在el-select中添加@change="change()

change(){
  this.$forceUpdate()
}

方法二：

 @change="currentSelect"
*******************************************
currentSelect(val) {
      this.$forceUpdate()
      console.log('选中的', val)
      if (val) {
        let obj = {}
        obj = this.options.find((item) => {
          return item.value === val //筛选出匹配数据
        })
        this.$set('', this.roadMark, val.value)
        this.value = obj.label
        console.log('选中的是', obj.label)
      } else {
        this.value = ''
        // this.$set('',this.roadMark, '')
      }
    },

方法三：

<el-table-column prop="roadMark"
                         label="标记">
          <template slot-scope="scope">
            <el-select v-model="scope.row[scope.column.property]"
                       clearable
                       placeholder="请选择"
                       @change="currentSelect">
              <el-option v-for="item in options"
                         :key="item.value"
                         :label="item.label"
                         :value="item.value">
              </el-option>
            </el-select>
          </template>
        </el-table-column>

前后加上template这个 解决