python - 通过循环通过 URL 传递参数

Question

因此，我尝试将 PDF 的名称传递给 URL，以便 View 可以显示相关的 PDF。

url.py

path('show-invoice/<str:invoice>', views.pdf_view, name ="pdfview")

View .py

def pdf_view(request, invoice):
    invoicename = Laptop.objects.get(invoice=invoice)
    invoicename = invoicename.invoice
    pdfpath = settings.MEDIA_ROOT + invoicename
    pdfpath = pdfpath.replace('/', '\\')
    try:
       return FileResponse(open(pdfpath, 'rb'), content_type='application/pdf')
    except FileNotFoundError:
       raise Http404()

模型.py

invoice = models.FileField(default='default.pdf', upload_to='uploads/')

发票列表.html

<h2>View invoices</h2>
{%for i in invoices%}
<ul>
   <li>
       <a href = "{%url 'laptops:pdfview' invoice=i.invoice%}"> {{i.invoice}} </a>
   </li>
</ul>
{%endfor%}

现在，我的问题是:为什么当我使用 invoice='default.pdf' 时它有效，而当我使用 invoice=i.invoice 时它不起作用？我收到以下错误

NoReverseMatch at /invoices/
Reverse for 'pdfview' with keyword arguments '{'invoice': 'uploads/default1.pdf'}' not found. 1 pattern(s) tried: ['show\\-invoice\\/(?P<invoice>[^/]+)$']

Answer 1

因为您在路径中使用的 str 转换器与发票属性中的 \ 不匹配。

您可以使用path转换器:

path('show-invoice/<path:invoice>', ...)