Output the file stream. When the user clicks to download, the output Content-Type is application/ms-excel. You can refer to the link description of this article

This is how I implemented it. The front-end page adds a click event to the export button. After clicking, use ajax to send data to the corresponding URL. Use xlrd to generate and save xlxs to the path specified by the server. Finally, return the file name (filename). Click the download button on the front-end. You can download it locally.

Front page:

<style type="text/css">
    @import "/static/order/jquery-ui.min.css";
</style>

<script type="text/javascript" src="/static/order/jquery-ui.min.js"></script>

<script type="text/javascript">
    $(function(){

        $('#export').click(function(){
            $('button').attr('disabled', 'disabled')
            $('button').text('正在处理，请耐心等待...')
            $('#download').hide()

            $.ajax({
                type: "POST",
                data: $('#order_filter_form').serialize(),
                url: "{{ url_for('.orders_export_search') }}",
                success: function(filename){
                    $('button').removeAttr('disabled')
                    $('button:first').text('筛选')
                    $('button:last').text('导出')

                    $('#download').show();
                    $('#download a').attr('href', "/static/order/export/"+filename)
                }
            })
            return false;
        })
    })
</script>

<p id="admin_order_control" class="well">
    <form class="form-inline" id="order_filter_form">
        <p class="col-md-2">
            <p class="form-group">
                <label for="status">订单状态</label>
                <select name="status" class="form-control">
                    <option value="">--请选择--</option>
                    <option value="0">关闭</option>
                    <option value="1">初始订单</option>
                    <option value="2">待支付</option>
                    <option value="3">订单处理中</option>
                </select>
            </p>

            <p class="form-group">
                <button type="submit" class="btn btn-primary">筛选</button>
                <button type="submit" class="btn btn-default" id="export">导出</button>
            </p>
            <p id="download" style="display:none;">
                <a href="#" class="btn btn-danger">点击下载导出文件</a>
            </p>
        </p>

        <p class="clearfix"></p>
    </form>
</p>

Server:

@admin_order_bp.route('/orders/export_search', methods=['POST'])
@json_view
def orders_export_search():
    user = request.environ['user']

    dict_item = {}
    for key in request.form:
        dict_item[key] = request.form[key]
    dict_item.update({'user_shop_ids':  user.shops})

    orders = Order.search(dict_item, {'page': 1, 'per_page': 99999})[0]
    filename = OrderExporter.rows_to_xls(orders)
    return filename

model layer:

# 根据数据生成excel文件
    @classmethod
    def rows_to_xls(cls, order_rows):
        filename = '%s_%s.xls' % (datetime.datetime.now().strftime("%Y%m%d"), cls.generate_random_str())
        filepath = '%s/%s' % (_updir, filename) # _updir就是文件的存放路径
        book = xlwt.Workbook(encoding="utf-8")
        sheet1 = book.add_sheet("Sheet 1")

        for i, val in enumerate(cls.csv_headline()):
            # （行，列，值）
            sheet1.write(0, i, val)

        for i, order_row in enumerate(order_rows):
            utf8_line = cls.order_line(order_row)
            for j, val in enumerate(utf8_line):
                sheet1.write(i+1, j, val)

        book.save(filepath)
        return filename