如何在laravel5.5中下载.csv文件。 没用

I am trying to export a database table using Laravel as a csv file. I have written down this code. I use it recently worked.But it is not working now.it's seems that everything ok .I do not know fix it

laravel 5.5 php 7 this is my button

<form action="{{route('manage.download')}}" method="POST"　enctype="multipart/form-data">

download

this is my class

class csv{

public function download($list, $header, $filename, $quot=true)
{

    if (count($header) > 0) {
        array_unshift($list, $header);
    }
    $stream = fopen('php://temp', 'r+b');

    foreach ($list as $row) {
        $this->_fputcsv($stream, $row,$quot);
    }
    rewind($stream);
    //$csv = str_replace("
", "
", stream_get_contents($stream));
    $csv = stream_get_contents($stream);
    $headers = array(
        'Content-Type' => 'text/csv',
        'Content-Disposition' => "attachment; filename=$filename",
    );

    return \Response::make($csv, 200, $headers);
}

private function _fputcsv($fp, $fields, $quot) {
    $tmp = array();
    foreach ($fields as $value) {
        if($quot){
            $value = str_replace('"', '""', $value);
            $tmp[]= '"'.$value.'"';
        }
        else{
            $tmp[]= $value;
        }
    }

    $str = implode(',', $tmp);
    $str .= "
";
    fputs($fp, $str);
}

}

this is my download function

public function csvdownload()
{
    //data
    $data = [
             0 => [
                'id'    => '1',
                'name'  => 'test1',
            ],
            1 =>[
                'id'    => '2',
                'name'  => 'test2',
            ],
            ....
    ];
    //CSV header
    $header = ['id', 'name'];
    //filename 
    $filename = Carbon::now()->format('YmdHis') . ".csv";

    //class
    CSV::download($data, $header, $filename, true);
}