Check the table header, and the front-end custom selects the exported columns as an excel table

The front end exports the table form to an excel form

First install the xlsx dependency, and then introduce import * as XLSX from 'xlsx' into the project;
after checking the table columns, you need to process the exported data.

 exportExcel() {
    
    
 //是否已勾选
    if (this.selectIndexs.length) {
    
    

      // tslint:disable-next-line: prefer-for-of 
      // this.body: 表格body 
      // this.head: 表格head
      for (let j = 0; j < this.body.length; j++) {
    
    
        const excelRow: object = {
    
    };
        this.selectIndexs.forEach(s => {
    
    
        // this.head : { value: label, checked: false }[] = [];
        // 注意：如果表头是一样的字符的话，导出的excel会合并到一列
          const name = this.head[s]['value'];
          // 如果值为空，用0填充
          excelRow[name] = isNil(this.body[j][s]) || this.body[j][s] === '' ? 0 : this.body[j][s];
        });
        this.excelTable.push(excelRow);
      }

    } else {
    
    
      this.message.error('请先选择表格字段!');
      return;
    }
    this.jsonToSheet(this.excelTable, 'excel.xls');
    this.excelTable = [];

  }

  jsonToSheet(json: any[], filename: string): void {
    
    
    const worksheet: XLSX.WorkSheet = XLSX.utils.json_to_sheet(json);
    const workbook: XLSX.WorkBook = XLSX.utils.book_new();
    XLSX.utils.book_append_sheet(workbook, worksheet, 'Sheet1');
    XLSX.writeFile(workbook, filename);
  }