【发布时间】：2019-05-09 19:35:51
【问题描述】：
如果不难，请告诉我如何正确编写脚本，以便在选择区域时仅显示该区域的城市，而在选择城市时仅显示该城市的地区。我需要这个来搜索。
型号：
class Region(models.Model):
name = models.CharField(max_length=100, verbose_name='Название области')
def __str__(self):
return self.name
class City(models.Model):
region = models.ForeignKey(Region, on_delete=models.CASCADE, verbose_name='Область')
name = models.CharField(max_length=100, verbose_name='Название города')
def __str__(self):
return self.name
class District(models.Model):
city = models.ForeignKey(City, on_delete=models.CASCADE, verbose_name='Город')
name = models.CharField(max_length=100, verbose_name='Название района')
def __str__(self):
return self.name
views.py 中的搜索功能：
def search(request):
districts = District.objects.all()
cities = City.objects.all()
regions = Region.objects.all()
queryset_list = Listing.objects.order_by('-list_date')
if 'region' in request.GET:
region_id = request.GET.get('region')
cities = City.objects.filter(region_id=region_id).order_by('name')
if region_id:
queryset_list = queryset_list.filter(region_id=region_id)
if 'city' in request.GET:
city_id = request.GET.get('city')
districts = District.objects.filter(city_id=city_id).order_by('name')
if city_id:
queryset_list = queryset_list.filter(city_id=city_id)
if 'district' in request.GET:
district_id = request.GET.get('district')
if district_id:
queryset_list = queryset_list.filter(district_id=district_id)
context = {
'districts': districts,
'cities': cities,
'regions': regions,
'listings': queryset_list,
'values': request.GET
}
return render(request, 'listings/search.html', context)
到目前为止，多亏了这个功能，整个地区、城市和地区的列表在模板中动态显示，搜索也可以，但必须依赖于选择。 搜索.html：
<form action="{% url 'search' %}">
<div class="form-row">
<div class="col-md-3 mb-3">
<label class="sr-only">Region</label>
<select name="region" class="form-control" id="id_region">
<option selected="true" disabled="disabled">Region</option>
{% for region in regions %}
<option value="{{ region.pk }}">{{ region.name }}</option>
{% endfor %}
</select>
</div>
<div class="col-md-3 mb-3">
<label class="sr-only">City</label>
<select name="city" class="form-control" id="id_city">
<option selected="true" disabled="disabled">City</option>
{% for city in cities %}
<option value="{{ city.pk }}">{{ city.name }}</option>
{% endfor %}
</select>
</div>
<div class="col-md-3 mb-3">
<label class="sr-only">District</label>
<select name="district" class="form-control" id="id_district">
<option selected="true" disabled="disabled">District</option>
{% for district in districts %}
<option value="{{ district.pk }}">{{ district.name }}</option>
{% endfor %}
</select>
</div>
</div>
<button class="btn btn-secondary btn-block mt-4" type="submit">Search</button>
</form>
我知道这是在 JS 上完成的，但我对它完全陌生，所以如果不难，请举个例子，在我的情况下脚本会是什么样子？提前非常感谢！
【问题讨论】：
标签： javascript json ajax django search