文件下载后删除文件

前端JS

function download()
    {
        if(downloadObj.hasClass('disabled')) {
            return false;
        }
        var filename = localStorage.getItem('filename');
        var url = '{{ url('admin/export/download') }}?filename=' + filename;
        location.href = url;
        localStorage.clear();
        // 禁用下载按钮
        downloadObj.addClass('disabled');
    }

后台方法

 public function download(Request $request)
    {
        if ($request->filled('filename')) {
            $filename = $request->input('filename');
        } else {
            $this->ajaxError(1, '文件不存在');
        }

        $header = [
            "Cache-Control" => "max-age=0",
            "Content-Description" => "File Transfer",
            'Content-disposition' =>  'attachment; filename=' . $filename,
            "Content-Type" => "application/zip",
            "Content-Transfer-Encoding" => "binary",
//            'Content-Length' =>  filesize($filename)
        ];
        return response()->download(public_path('/storage/'. $filename), $filename, $header)->deleteFileAfterSend(true);
    }

当我点击下载按钮后，请求后台方法，如果文件太大的话，会有延迟，但是还没有等我下载完就删除文件了。。。

各位有此问题吗？求指点