Use VUE to realize excel export data

Article directory

• foreword
• 1. Front-end interface
• Two, package js file
  • 1. Write method and import
  • 2. Acquire data, process data
• Summarize

---

foreword

Some time ago, I needed to add a data export function to an interface. According to the previous thinking method, I usually export excel through the back-end interface. In fact, many project frameworks now have this function packaged. After I encountered this requirement, I first found that it was not in the framework of the project, and then I have been learning Vue recently, so I want to use Vue to realize this function. Don't talk nonsense and do it yourself .

1. Front-end interface

First of all, an export button is introduced on the interface (here I use the element ui framework)

<el-button type="primary" icon="el-icon-download" size="small" @click="exportExcel">导出</el-button>

2. Introduce the written js file (it is used to construct the interface of the excel table)

import {export_json_to_excel} from '@/util/exportExcel.js'

1. The code of the imported export_json_to_exce method is as follows:

import XLSX from 'xlsx' (remember to import xlsx in the js file)

export function export_json_to_excel({
                                       header,
                                       data,
                                       filename,
                                       autoWidth = true,
                                       bookType=  'xlsx'
                                     } = {}) {
  /* original data */
  filename = filename || 'excel-list'
  data = [...data]
  data.unshift(header);
  var ws_name = "SheetJS";
  var wb = new Workbook(),
    ws = sheet_from_array_of_arrays(data);

  if (autoWidth) {
    /*设置worksheet每列的最大宽度*/
    const colWidth = data.map(row => row.map(val => {
      /*先判断是否为null/undefined*/
      if (val == null) {
        return {
          'wch': 10
        };
      }
      /*再判断是否为中文*/
      else if (val.toString().charCodeAt(0) > 255) {
        return {
          'wch': val.toString().length * 2
        };
      } else {
        return {
          'wch': val.toString().length
        };
      }
    }))
    /*以第一行为初始值*/
    let result = colWidth[0];
    for (let i = 1; i < colWidth.length; i++) {
      for (let j = 0; j < colWidth[i].length; j++) {
        if (result[j]['wch'] < colWidth[i][j]['wch']) {
          result[j]['wch'] = colWidth[i][j]['wch'];
        }
      }
    }
    ws['!cols'] = result;
  }

  /* add worksheet to workbook */
  wb.SheetNames.push(ws_name);
  wb.Sheets[ws_name] = ws;

  var wbout = XLSX.write(wb, {
    bookType: bookType,
    bookSST: false,
    type: 'binary'
  });
  saveAs(new Blob([s2ab(wbout)], {
    type: "application/octet-stream"
  }), `${filename}.${bookType}`);
}

function sheet_from_array_of_arrays(data, opts) {
  var ws = {};
  var range = {
    s: {
      c: 10000000,
      r: 10000000
    },
    e: {
      c: 0,
      r: 0
    }
  };
  for (var R = 0; R != data.length; ++R) {
    for (var C = 0; C != data[R].length; ++C) {
      if (range.s.r > R) range.s.r = R;
      if (range.s.c > C) range.s.c = C;
      if (range.e.r < R) range.e.r = R;
      if (range.e.c < C) range.e.c = C;
      var cell = {
        v: data[R][C]
      };
      if (cell.v == null) continue;
      var cell_ref = XLSX.utils.encode_cell({
        c: C,
        r: R
      });

      if (typeof cell.v === 'number') cell.t = 'n';
      else if (typeof cell.v === 'boolean') cell.t = 'b';
      else if (cell.v instanceof Date) {
        cell.t = 'n';
        cell.z = XLSX.SSF._table[14];
        cell.v = datenum(cell.v);
      } else cell.t = 's';

      ws[cell_ref] = cell;
    }
  }
  if (range.s.c < 10000000) ws['!ref'] = XLSX.utils.encode_range(range);
  return ws;
}

2. Get data

The code is as follows (this part of the code is the vue interface we import the button)

​
exportExcel: throttle(function () {
    //这个是请求数据的接口（我这里懒省事，直接调的页面table的接口，给size传了个999999）
      findList({
        userName: this.query.userName
        page: this.page.currentPage,
        size: 9999999
      })
        .then(res => {
          let json_data = res.data
          if(json_data.length <= 0){
            this.$message.error('导出数据为空，请先搜索内容')
            return false
          }
          let tHeader = ["单号", "状态","部门","工号","姓名","邮箱"]
          let filterVal = ["objectId","status","dept","usrId","userName","email"]
          let excelList = json_data
          let filename='申请明细列表'+ excelNameTime()
          let data = this.formatJson(filterVal, excelList);
          export_json_to_excel({
            header:tHeader,
            data,
            filename
          })
        })
        .catch(error => {
          reject(error);
        })
    }, 2000),
    //这个方法是对数据进行处理的，比如说状态返回的可能是数字，而excel里要展示的是文字
    formatJson(filterVal, excelList) {
      let that = this
      return excelList.map(v =>
        filterVal.map(j => {
          if (j === "status") {
            if(v.status == '0'){
              return "待审批"
            } else if(v.status == '1'){
              return '审批通过"
            } else if(v.status == '2'){
              return "审批不通过"
            }
          }
          return v[j];
        })
      );
    },

​

In the above part of the code, there is a time processing method I wrote and a throttle (it is recommended to create a util.js file to import, I have a new js file here)

 import {excelNameTime,throttle} from '@/util/util'

export const throttle = (fn, gapTime) => {
  if (gapTime == null || gapTime == undefined) {
    gapTime = 1500
  }
  let _lastTime = null
  // 返回新的函数
  return function () {
    let _nowTime = + new Date()
    if (_nowTime - _lastTime > gapTime || !_lastTime) {
      fn.apply(this, arguments)   //将this和参数传给原函数
      _lastTime = _nowTime
    }
  }
}

export const excelNameTime = () =>{
  var myDate = new Date();
  var mon = myDate.getMonth() + 1; //getMonth()返回的是0-11，则需要加1
  if (mon <= 9) {
    mon = "0" + mon; //如果小于9的话，则需要加上0
  }
  var day = myDate.getDate(); //getdate()返回的是1-31，则不需要加1
  if (day <= 9) {
    day = "0" + day; //如果小于9的话，则需要加上0
  }
  return (myDate.getFullYear().toString() +
    mon.toString() +
    day.toString() +
    myDate.getHours().toString() +
    myDate.getMinutes().toString() +
    myDate.getSeconds().toString())
}

---

Summarize

以上就是使用vue的完整导出功能了，其实对于后端，没有什么要求，只要返回要导出的数据就可以了。谢谢各位学习！