laravel5.7导出excel文件

//ExportMulSheets.php

namespace App\Exports;

use Maatwebsite\Excel\Concerns\Exportable;
use Maatwebsite\Excel\Concerns\WithMultipleSheets;

class ExportMulSheets implements WithMultipleSheets
{
    use Exportable;

    private $size;
    private $myArray;
    private $myHeadings;
    private $sheetNames;
    private $columns;

    public function __construct($size, $myArray, $myHeadings, $sheetNames, $columns)
    {
        $this->size = $size;
        $this->myArray = $myArray;
        $this->myHeadings  = $myHeadings;
        $this->sheetNames = $sheetNames;
        $this->columns = $columns;
    }

    /**
     * @return array
     */
    public function sheets(): array
    {
        $sheets = [];
        for ($i = 0; $i < $this->size; $i++) {
            $sheets[] = new ExportSheet($this->myArray[$i], $this->myHeadings[$i], $this->sheetNames[$i], $this->columns[$i]);
        }
        return $sheets;
    }
}

//ExportSheet.php

namespace App\Exports;

use Maatwebsite\Excel\Concerns\WithHeadings;
use Maatwebsite\Excel\Concerns\FromArray;
use Maatwebsite\Excel\Concerns\WithTitle;
use Maatwebsite\Excel\Concerns\ShouldAutoSize;
use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
use Maatwebsite\Excel\Concerns\WithColumnFormatting;

class ExportSheet implements FromArray, WithHeadings, WithTitle, ShouldAutoSize, WithColumnFormatting
{
    private $myArray;
    private $myHeadings;
    private $title;
    private $columns;

    public function __construct($myArray, $myHeadings, $title, $columns = [])
    {
        $this->myArray = $myArray;
        $this->myHeadings = $myHeadings;
        $this->title = $title;
        $this->columns = $columns;
    }

    public function array(): array
    {
        return $this->myArray;
    }

    public function headings(): array
    {
        return $this->myHeadings;
    }

    public function title(): string
    {
        return $this->title;
    }

    public function columnFormats(): array
    {
        return $this->columns;
    }
}

use App\Exports\ExportMulSheets;
use Excel;
use PhpOffice\PhpSpreadsheet\Style\NumberFormat;

$columns = ['F' => NumberFormat::FORMAT_PERCENTAGE_00]; //用于sheet列的格式设定 
$excel = Excel::download(new ExportMulSheets(1, [$data], [$header], [$sheetName], [$columns]), $xlsFileName); 
return $excel;