vue通过查询数据进行table数据导出时报错

进行又给table数据导出，以拿到查询的数据，
进行导出时，报这个错，时什么意思

<template>

  <div>
    <el-button size="small" type="primary"  @click="chaxun"
    >查询</el-button>

    <div class="block">
      <span class="demonstration"></span>
      <el-date-picker
        v-model="datetimeone"
        type="datetimerange"
        start-placeholder="开始日期"
        end-placeholder="结束日期"
        value-format="yyyy-MM-dd HH:mm:ss"
        :default-time="['12:00:00']">
      </el-date-picker>

    </div>


    <el-table id="weektab"
              :data="tableData"
              style="width:360px"
              :header-cell-style="{textAlign: 'center'}"
              :cell-style="{ textAlign: 'center' }"    >
      <el-table-column
        prop="username"
        width="180px"
        label="日期">
      </el-table-column>
      <el-table-column
        prop="password"
        width="180px"
        label="姓名">
      </el-table-column>
    </el-table>
    <el-button size="small" type="primary" @click="exportExcel"
    >导出excel</el-button>
  </div>
</template>

<script>
import FileSaver from 'file-saver'
import XLSX from 'xlsx'
const Exceljs=require("exceljs")

export default {
  name: "Login",
  data() {
    return {
      tableData: [],
      twoon:[],
      datetimeone:'',
      testTime:{
        startTime:'',
        endTime:''
      }

    }
  },

  methods:{
    chaxun() {
      if(this.datetimeone.length=='0'){
        this.testTime.startTime=undefined;
        this.testTime.endTime=undefined;
        this.$alert("清输入日期",'提示',{
          confirmButtonText:'确定',
          type:'warning'
        })
      }else{
        this.testTime.startTime=this.datetimeone[0];
        this.testTime.endTime=this.datetimeone[1];
        console.log(this.testTime.startTime)
        console.log(this.testTime.endTime)
        this.$axios.post('http://localhost:8899/api/xun',this.testTime,{headers:{'Content-Type':"application/json"}}).then(
          ((resp) => {
            this.tableData=resp.data;  /*回调函数使用箭头函数进行回调    实现vue一个简单的查询 */

          })
        )
      }

    },

    /*定义导出事件*/
    exportExcel(){
   /*   var xlsxParam={raw:true}
      /!*从表生成工作簿对象*!/
      var wb=XLSX.utils.table_to_book(
        document.querySelector("#weektab"),
        xlsxParam
      );
      /!*获取二级制字符串为输出*!/
      var wbout=XLSX.write(wb,{
        bookType:'xlsx',
        bookSST:true,
        type:'array',
      });
      try {
        FileSaver.saveAs(
          new Blob([wbout],{type:'application/octet-stream'}),
          "sheetjs.xlsx"
        );
      }catch (e){
        if(typeof  console!=="nudefined")console.log(e,wbout);
      }
      return wbout;*/
      let valueDate=this.datetimeone;
      let examExcels=this.tableData;
      const workbook=new Exceljs.Workbook();
      workbook.creator='使用情况';
      workbook.lastModifiedBy='使用情况';
      workbook.created=new Date();
      workbook.modified=new Date();

      workbook.properties.date1904=true;
      const worksheet=workbook.addWorksheet("使用情况");
      worksheet.properties.defaultColWidth=16;
      worksheet.properties.defaultRowHeight=16;

      /*定义第一个表*/
      const Examrow=worksheet.getRow(1);
      Examrow.height=50;
      const Examcell=worksheet.getCell("A1");
      worksheet.mergeCells("A1:B1");
      Examcell.value='表一';
      Examcell.font={name:"宋体",family:4,size:14,bold:true};
      Examcell.alignment={vertical:'middle',horizontal:'center'};

      worksheet.addTable({
        name:"examTable",
        ref:'A2',
        displayName:'考试计划',
        headerRow:true,
        filterButton:false,
        totalsRow:false,
        style:{
          theme:'TableStyleLight8',
        },
        columns:[
          {name:'公司'},
          {name:'测试'},
        ],
        rows:examExcels,
      });

      workbook.xlsx.writeBuffer().then((buffer) => {

        FileSaver.saveAs(
          new Blob([buffer], {
            type: "application/octet-stream",
          }),
          `${valueDate[0]}-${valueDate[1]}使用情况.xlsx`
        );
      });
    }
  }
}
</script>

<style scoped>


</style>

应该是tableData的数据格式不对吧

这个是库里的问题 。大概率是数据 不规范 。你可以先用简单的数据测试一下

点击定位下login.vue控制台的哪行报错了，