Django 3.0：鉴于模板中的选定选项无法获取价值

Question

我是 django 的初学者。而且，我无法查看用户选择的选项的值。我必须在那里应用一些逻辑。

views.py

def shop(request):

    if request.GET.get('featured'):
        featured_filter = request.GET.get('featured')
        print(featured_filter) #debugging purpose
    else:
        print("\n\nnone\n\n") #debugging purpose

    bookz = Book.objects.order_by('title')
    var = {'books': bookz, 'range': 10}
    return render(request, 'bookrepo/shop.html', context=var)

shop.html

<form action="{% url 'bookrepo:shop' %}" method="GET">
    <select name="featured" class="custom-select-lg custom-select">
        <option selected><h1>Filter</h1></option>
        <option value="pricelow">Low price</option>
        <option value="pricehigh">High price</option>
        <input type="submit" name="featured" value="Filter" />
    </select>
</form>

这些选项与模型无关。 所以现在，当我选择低价并按下按钮时，我得到了这个：（在 django 控制台中）

[10/May/2020 00:18:20] "GET /shop/?featured=pricehigh&featured=Filter HTTP/1.1" 200 47486
[10/May/2020 00:18:20] "GET /static/js/js.dom.changer.js HTTP/1.1" 304 0
Filter
[10/May/2020 00:18:24] "GET /shop/?featured=pricelow&featured=Filter HTTP/1.1" 200 47486

如您所见，“过滤器”正在打印。但我想要的是特色的价值，比如 pricelow 或 pricehigh。

Answer 1

发生这种情况的原因是因为您的请求有 两个 featured 值：pricehigh 和 Filter，实际上：

/shop/?<b>featured=pricehigh</b>&amp;<b>featured=Filter</b>

第二个是由submit 按钮引起的。您可以简单地从按钮中删除 name="…" 属性：

<form action="{% url 'bookrepo:shop' %}" method="GET">
    <select name="featured" class="custom-select-lg custom-select">
        <option selected><h1>Filter</h1></option>
        <option value="pricelow">Low price</option>
        <option value="pricehigh">High price</option>
        <input type="submit" value="Filter" />
    </select>
</form>