前端通过json数据导出excel表格文件（支持多级表头、复杂表头）（json转excel）

downloadBmExcel(){
	    		let vm = this;
	    		let titles = ["顺序号","责任者","文号","标题","日期","页号","备注"];
	    		let keys = ['index',null,null,'name',null,'range',null];
				let groups = [];
				vm.groups.map((v)=>{
					if(!v.type){
						groups.push(v);
					}
				})
	    		JSONToExcelConvertor(groups,vm.volumeName+"_智能编目目录",titles,keys);
	    	},
	    	
console.log(groups)//数据格式
					//0:
					//editing: false
					//id: "c9e9bc6b8a200001c9eb127049c02a00"
					//index: 0
					//ismulu: true
					//list: Array(3)
					//name: "讯问笔录（（被告）第1次"
					//range: "1-3"
					//respon: ""
					//select: false

封装
export function JSONToExcelConvertor (JSONData, FileName, title, keys, notital, titleH) {
  if (!JSONData) { return }
    // 转化json为object
  var arrData = typeof JSONData !== 'object' ? JSON.parse(JSONData) : JSONData

  var excel = ''

    // 设置表头
  var row = notital ? '' : "'

  if (title) {
        // 使用标题项
    for (var i in title) {
      row += "'
    }
  } else {
        // 不使用标题项
    for (var i in arrData[0]) {
      row += "'
    }
  }

  excel += row + ''

    // 设置数据
  for (var i = 0; i < arrData.length; i++) {
    var row = ''
    for (var k in title) {
      if (!keys[k]) {
        row += ""
      } else {
        row += "'
      }
    }
        // for (var index in arrData[i]) {
        //     //判断是否有过滤行
        //     if(filter)
        //     {
        //         if(filter.indexOf(index)==-1)
        //         {
        //              var value = arrData[i][index] == null ? "" : arrData[i][index];
        //              row += '';
        //         }
        //     }
        //     else
        //     {
        //          var value = arrData[i][index] == null ? "" : arrData[i][index];
        //          row += "";
        //     }
        // }
    excel += row + ''
  }

  excel += '
" + (titleH || '卷内文件目录') + '
" + title[i] + '
" + i + '
" + arrData[i][keys[k]] + '
' + value + '
" + value + "
'

  var excelFile = ""
  excelFile += ''
  excelFile += ''
  excelFile += ''
  excelFile += ''
  excelFile += ''
  excelFile += excel
  excelFile += ''
  excelFile += ''

  var uri = 'data:application/vnd.ms-excel;charset=utf-8,' + encodeURIComponent(excelFile)

  var link = document.createElement('a')
  link.href = uri

  link.style = 'visibility:hidden'
  link.download = FileName + '.xls'

  document.body.appendChild(link)
  link.click()
  document.body.removeChild(link)
}