我正在将查询集列表和总价格列表传递给模板。我使用我的申请表的反向关系来显示该申请存在的每一行。我正在传递请购单的总价（将所有行的价格加在一起）。我正在尝试以表格格式显示每条记录，并在提交按钮旁边的底部显示累积价格。我最初的想法显然是遍历该列表，但这给我带来了一个问题，因为我将嵌套三个for循环，因此不会显示预期的结果。
<h1>Pending Action</h1>
{% for req_header in req_header_list %}
<div class="accordion" id="accordionExample">
<div class="card">
<div class="card-header" id="headingOne">
<h5 class="mb-0">
<button class="btn btn-link" type="button" data-toggle="collapse" data-target="#req{{ req_header.id }}" aria-expanded="false" aria-controls="collapseOne">
{{ req_header }}
</button>
</h5>
</div>
<div id="req{{ req_header.id }}" class="collapse" aria-labelledby="headingOne" data-parent="#accordionExample">
<div class="card-body">
<table class="table">
<tr>
<th>Line</th>
<th>Description</th>
<th>Quantity</th>
<th>Total Price</th>
<th>Status</th>
</tr>
{% for line in req_header.par_req_line.all %}
<tr>
<td>{{line}}</td>
<td>{{line.description}}</td>
<td>{{line.quantity}}</td>
<td>{{line.total_price}}<td>
<td>{{line.status}}</td>
</tr>
{% endfor %}
<tr>
<td>
<form action="#" method="POST">
<input type="submit" value="Submit">
</form>
</td>
<td></td>
<td></td>
<td>
<!--WANT TO DISPLAY THE TOTAL PRICE PER REQUISITION HERE
{{price_list.0}}
</td>
</tr>
</table>
</div>
</div>
</div>
</div>
{% endfor %}
</div>
def pending_action(request):
user = CustomUser.objects.get(username=request.user)
user_req_headers = Requisition.objects.filter(username=user)
complete_status = RequisitionStatus.objects.get(status='Completed')
req_header_list = []
total_price = 0
price_list = []
for req_header in user_req_headers:
req_lines = RequisitionLine.objects.filter(Q(parent_req = req_header) & ~Q(status=complete_status))
for line in req_lines:
if line.parent_req not in req_header_list:
req_header_list.append(line.parent_req)
total_price = total_price + line.total_price
price_list.append(total_price)
total_price = 0
return render(request, 'req/pending_action.html', {'req_header_list':req_header_list, 'price_list':price_list})
class Requisition(models.Model):
username = models.ForeignKey(
'users.CustomUser', on_delete=models.CASCADE, related_name='req_user')
signature = models.CharField(max_length=10, blank=True, null=True)
class RequisitionLine(models.Model):
parent_req = models.ForeignKey('Requisition', on_delete=models.CASCADE, related_name='par_req_line' )
sequence = models.PositiveIntegerField()
item_code = models.ForeignKey(
'items.ItemMaster', on_delete=models.CASCADE, related_name='req_item', blank=True, null=True)
description = models.CharField(max_length=50, blank=True)
extra_information = models.TextField(blank=True)
quantity = models.PositiveIntegerField(blank=True, default=0,null=True)
price = models.DecimalField(max_digits=19, decimal_places=2, blank=True, default=0.00,null=True)
total_price = models.DecimalField(max_digits=19, decimal_places=2, blank=True, default=0.00,null=True)
purchase_order = models.CharField(max_length=9, blank=True,null=True)
po_line = models.PositiveSmallIntegerField(blank=True,null=True)
req_delivery_date = models.DateField(blank=True,null=True)
act_delivar_date = models.DateField(blank=True, null=True)
status = models.ForeignKey('RequisitionStatus', related_name='req_status', on_delete=models.CASCADE, blank=True, null=True)
assistance = models.ForeignKey('users.UserRoles', related_name='req_assist', blank=True, null=True, on_delete=models.CASCADE, limit_choices_to= ~Q(role='Requestor'))
catagory = models.ForeignKey('items.ItemCatagory', on_delete=models.CASCADE, related_name='line_cat', blank=True, null=True)
notes = models.TextField(blank=True)
class Meta:
unique_together = ('parent_req','sequence')
Environment:
Request Method: GET
Request URL: http://127.0.0.1:8000/req/pending/
Django Version: 2.1
Python Version: 3.7.0
Installed Applications:
['django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'req',
'users.apps.UsersConfig',
'items']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware']
Traceback:
File "C:\Users\###\Documents\Python\venv\env\lib\site-packages\django\core\handlers\exception.py" in inner
34. response = get_response(request)
File "C:\Users\###\Documents\Python\venv\env\lib\site-packages\django\core\handlers\base.py" in _get_response
126. response = self.process_exception_by_middleware(e, request)
File "C:\Users\###\Documents\Python\venv\env\lib\site-packages\django\core\handlers\base.py" in _get_response
124. response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\Users\###\Documents\Python\venv\env\lib\site-packages\django\contrib\auth\decorators.py" in _wrapped_view
21. return view_func(request, *args, **kwargs)
File "C:\Users\###\Documents\Python\django\lambda\req\views.py" in pending_action
273. user_reqs = Requisition.objects.filter(par_req_line__in=user_req_lines_incomplete).annotate(aggregated_price=sum('par_req_line__total_price'))
Exception Type: TypeError at /req/pending/
Exception Value: unsupported operand type(s) for +: 'int' and 'str'
答案 0 :(得分：0)
您应该重构您的views.py以返回与您的条件匹配的单个Requisition对象的查询集，并用您要提供的汇总价格数据进行注释。然后，您需要重构您的html模板以遍历单个查询集。最大限度地使用Django ORM将使您的代码更短，并且运行速度更快。
from django.db.models import Sum
def pending_action(request):
user_req_lines_incomplete = RequisitionLine.objects.filter(parent_req__username=request.user).exclude(status__status='Completed'))
user_reqs = Requisition.objects.filter(par_req_line__in=user_requisition_lines_incomplete).annotate(aggregated_price=Sum('par_req_line__total_price'))
return render(request, 'req/pending_action.html', {'user_reqs':user_reqs})
请注意，在对模型进行注释之前，在相关模型上进行过滤时，Django ORM的内部存在一些诡计。当您filter(par_req_line__in时，这也意味着将仅在符合过滤条件的par_req_line上计算该行后面出现的注释。因此，您的汇总将仅汇总user_req_lines_incomplete中的行。我有95％的把握是您想要的，但是如果您正在寻找其他条件，请随时澄清。为了让您的所有代码都带有许多for循环和名称，我有些挣扎。 （没有判断力。）
<!-- I took out most of your HTML to simplify -->
<h1>Pending Action</h1>
{% for req in user_reqs %}
<h5>{{req}}</h5> <!-- You can show whatever you want for your req here -->
{% for line in req.par_req_line.all %x}
<tr>
<td>{{line}}</td>
<td>{{line.description}}</td>
<td>{{line.quantity}}</td>
<td>{{line.total_price}}<td>
<td>{{line.status}}</td>
</tr>
{% endfor %}
Total price: {{req.aggregated_price}} <!-- Use the annotated data here -->
{% endfor %}
希望有帮助。