使用maatwebsite excel 2.0.8和laravel 5.2错误导出到excel-无法访问此页面

如何解决使用maatwebsite excel 2.0.8和laravel 5.2错误导出到excel-无法访问此页面

我的系统中出现一个奇怪的错误，在我的public function exportSales()中使用maatwebsite excel导出功能非常成功，但是调用 public function exportInventory时却无效。下面是我对这两个函数的代码。

SaleController.PHP

此功能有效并下载SalesReport.xls

public function exportSales( $param = null ){

    ob_end_clean();
    ob_start();

    $arrayMonths = ["January","February","march","April","May","June","July","August","September","October","November","December"];

    if( !$param ){

      Excel::create('SalesReport',function($excel){
      $excel->sheet('sales_sheet',function($sheet){
      $sales = Sale::orderBy('created_at','desc')->get();
      $sheet->loadView('sales/view_sales_excel',[ 'sales' => $sales ]);

      });

     })->download('xls');

    } else if( in_array( ucfirst( $param ),$arrayMonths ) ){

      Excel::create('SalesReport',function($excel) use($param){
      $excel->sheet('sales_sheet',function($sheet) use($param){
      $sales = Sale::orderBy('created_at','desc')
                         ->where('month','ILIKE','%'.$param.'%')
                         ->get();
      $sheet->loadView('sales/view_sales_excel',[ 'sales' => $sales ]);

      });

     })->download('xls');                   

  }else{

    return redirect()->back()->with('message','Cannot export with a parameter '.$param.'. Please contact developer for additional functions needed. Thank you.');

  }

}

InventoryRecordController.PHP

此功能不起作用，返回的错误无法达到此页面错误

public function exportInventory( $param = null ){

    ob_end_clean();
    ob_start();

    if( !$param ){

      Excel::create('InventoryReport',function($excel){

        $excel->sheet('inventory_sheet',function($sheet){

          $inventory = InventoryRecord::orderBy('created_at','desc')->get();
          $sheet->loadView('inventory/view_inventory_excel',[ 'inventory' => $inventory ]);

        });

      })->download('xls');

                          
    } else{

      /*$products = InventoryRecord::orderBy('pharmaceutical','asc')
                         ->where('type','%'.$param.'%')
                         ->orwhere('unit','%'.$param.'%')
                         ->get();*/
      return redirect()->back()->with( 'message','Cannot export with the parameter '.$param.'. Please contact developer for additional functions needed. Thank you.' );                   

    }

}

以下是我的代码编辑器的屏幕截图：

也请注意我正在使用7.2.12版本的xampp，也许这件事吗？请帮我解决这个问题。谢谢。