Export2Excel.js

/* eslint-disable */
// 1:下载  file-saver    xlsx,如果出现问题，如果以前是yarn,先执行yarn  如果还不行，再执行npm i 再运行，如果还不行自行调整版本 yarn add 插件名@版本号
//
// 文件下载生成
import { saveAs } from 'file-saver'
// 生成excel与解析excel数据
import XLSX from 'xlsx'

function generateArray(table) {
  var out = []
  var rows = table.querySelectorAll('tr')
  var ranges = []
  for (var R = 0; R < rows.length; ++R) {
    var outRow = []
    var row = rows[R]
    var columns = row.querySelectorAll('td')
    for (var C = 0; C < columns.length; ++C) {
      var cell = columns[C]
      var colspan = cell.getAttribute('colspan')
      var rowspan = cell.getAttribute('rowspan')
      var cellValue = cell.innerText
      if (cellValue !== '' && cellValue == +cellValue) cellValue = +cellValue

      //Skip ranges
      ranges.forEach(function (range) {
        if (
          R >= range.s.r &&
          R <= range.e.r &&
          outRow.length >= range.s.c &&
          outRow.length <= range.e.c
        ) {
          for (var i = 0; i <= range.e.c - range.s.c; ++i) outRow.push(null)
        }
      })

      //Handle Row Span
      if (rowspan || colspan) {
        rowspan = rowspan || 1
        colspan = colspan || 1
        ranges.push({
          s: {
            r: R,
            c: outRow.length
          },
          e: {
            r: R + rowspan - 1,
            c: outRow.length + colspan - 1
          }
        })
      }

      //Handle Value
      outRow.push(cellValue !== '' ? cellValue : null)

      //Handle Colspan
      if (colspan) for (var k = 0; k < colspan - 1; ++k) outRow.push(null)
    }
    out.push(outRow)
  }
  return [out, ranges]
}

function datenum(v, date1904) {
  if (date1904) v += 1462
  var epoch = Date.parse(v)
  return (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000)
}

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
}

function Workbook() {
  if (!(this instanceof Workbook)) return new Workbook()
  this.SheetNames = []
  this.Sheets = {}
}

function s2ab(s) {
  var buf = new ArrayBuffer(s.length)
  var view = new Uint8Array(buf)
  for (var i = 0; i != s.length; ++i) view[i] = s.charCodeAt(i) & 0xff
  return buf
}

export function export_table_to_excel(id) {
  var theTable = document.getElementById(id)
  var oo = generateArray(theTable)
  var ranges = oo[1]

  /* original data */
  var data = oo[0]
  var ws_name = 'SheetJS'

  var wb = new Workbook(),
    ws = sheet_from_array_of_arrays(data)

  /* add ranges to worksheet */
  // ws['!cols'] = ['apple', 'banan'];
  ws['!merges'] = ranges

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

  var wbout = XLSX.write(wb, {
    bookType: 'xlsx',
    bookSST: false,
    type: 'binary'
  })

  saveAs(
    new Blob([s2ab(wbout)], {
      type: 'application/octet-stream'
    }),
    'test.xlsx'
  )
}
// 将json数据转换成excel并提供下载
// header：头部  ['姓名','转正时间'...]
// data:列表数据  [['张三'，‘2021-12-01’...]]
// filename:下载的文件名,默认是excel-list
export function export_json_to_excel({
  multiHeader = [],
  header,
  data,
  filename,
  merges = [],
  autoWidth = true,
  bookType = 'xlsx'
} = {}) {
  /* original data */
  filename = filename || 'excel-list'
  data = [...data]
  data.unshift(header)

  for (let i = multiHeader.length - 1; i > -1; i--) {
    data.unshift(multiHeader[i])
  }

  var ws_name = 'SheetJS'
  var wb = new Workbook(),
    ws = sheet_from_array_of_arrays(data)

  if (merges.length > 0) {
    if (!ws['!merges']) ws['!merges'] = []
    merges.forEach((item) => {
      ws['!merges'].push(XLSX.utils.decode_range(item))
    })
  }

  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
          }
        } else if (val.toString().charCodeAt(0) > 255) {
          /*再判断是否为中文*/
          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}`
  )
}