if语句不能在Django模板中工作

Question

模板if循环中的for语句不起作用。它仍然显示不可用的项目。 这是我模板的代码

形状template.html

{% for field in form %}
{% if eventprojector.projector.available %}
    <div class="form-group">
    <div class="col-sm-offset-2 col-sm-10">
    <span class="text-danger small">{{ field.errors }} </span>
    </div>
    <label class="control-label col-sm-2">{{ field.label_tag }} </label>
    <div class ="col-sm-10">{{ field }} </div>
    </div>
{%endif %}
{% endfor %}

Answer 1

以下是重构代码，它将根据您的代码对可用和不可用的项目起作用：

<强>事件/ models.py：

from django.db import models

# Create your models here.
class Projectors(models.Model):
    pro = models.CharField(max_length=50)
    available = models.BooleanField(default=True)
    def __str__(self):
        return self.pro

class Eventprojector(models.Model):
    projector = models.ForeignKey(Projectors)
    date = models.DateField(blank=True, null=True)
    start = models.CharField(max_length=50, null=True)
    end = models.CharField(max_length=50, null=True)
    is_accept = models.IntegerField(default=0)

    def get_absolute_url(self):
        return reverse( 'retest:eventprojectorform')
    def __str__(self):
        return str(self.id)

<强>事件/ urls.py：

from django.conf.urls import url

from . import views

urlpatterns = [
    # ex: /event/1/
    url(r'^(?P<eventprojector_id>[0-9]+)/$', views.projectoraccept, name='projectoraccept'),
]

<强>事件/ views.py：

from django.shortcuts import render, get_object_or_404
from .models import Eventprojector
# Create your views here.

def projectoraccept(request, eventprojector_id):
    eventprojector = get_object_or_404(Eventprojector, pk=eventprojector_id)
    eventprojector.is_accept = eventprojector.is_accept+1
    eventprojector.save(update_fields=['is_accept'])
    if eventprojector.is_accept == 3:
        eventprojector.projector.available = False
        eventprojector.projector.save(update_fields=['available'])
    return render(request, 'event/projectordetails.html' , {'eventprojector' : eventprojector })

<强> statckoverflow / urls.py：

from django.conf.urls import url, include
from django.contrib import admin

urlpatterns = [
    url(r'^event/', include('event.urls')),
    url(r'^admin/', admin.site.urls),
]

<强>计算器/事件/模板/事件/ projectordetails.html：

{% if eventprojector.projector.available %}
    <div class="form-group">
    <div class="col-sm-offset-2 col-sm-10">
    <span class="text-danger small">TEST</span>
    </div>
    <label class="control-label col-sm-2">TESTTEST</label>
    <div class ="col-sm-10">TESTETST</div>
    </div>
{% endif %}

设置完所有环境后，通过管理控制台将一些测试数据添加到表中：

event_projectors: pro = 'TEST1' and available= True
event_eventprojector :  projector = 'TEST1' date = today, start = 1, end = 2, is_accept = 1

然后运行服务器开始测试：

1，当您第一次输入http://127.0.0.1:8000/event/1/时，它将显示如下形式:(此处'event_jecter中的'is_accept'字段将加1为2，检查视图功能）

<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<span class="text-danger small">TEST</span>
</div>
<label class="control-label col-sm-2">TESTTEST</label>
<div class ="col-sm-10">TESTETST</div>
</div>

2，当您再次输入网址http://127.0.0.1:8000/event/1/时，eventprojector中的'is_accept'字段将再次加1为3，然后它将设置eventprojector.projector.available = False，此处您无法看到该元素，它在模板中是空的。

希望上面的代码可以帮助您正确地使用参数eventprojector渲染模板projectordetails.html，请注意渲染函数render(request, 'event/projectordetails.html' , {'eventprojector' : eventprojector })将仅使用参数event/projectordetails.html呈现给tempalte eventprojector。可能你的模板有些不匹配？

Answer 2

models.py

class Projectors(models.Model):
pro = models.CharField(max_length=50)
sec = models.ForeignKey(Section)
available = models.BooleanField(default=True)
def __str__(self):
             return self.pro 
class Eventprojector(models.Model):
projector = models.ForeignKey(Projectors)
date = models.DateField(blank=True, null=True)
start = models.CharField(max_length=50, null=True)
end = models.CharField(max_length=50, null=True)
is_accept = models.IntegerField(default=0)

def get_absolute_url(self):
    return reverse( 'retest:eventprojectorform')
def __str__(self):
             return str(self.id)

views.py

def projectoraccept(request, eventprojector_id):
eventprojector = get_object_or_404(Eventprojector, pk=eventprojector_id)
if request.method == 'POST':
    eventprojector.is_accept = eventprojector.is_accept+1
    eventprojector.save(update_fields=['is_accept'])
        if eventprojector.is_accept == 3:
            if eventprojector.projector.sec.sec_name == 'CS_dept':
                eventprojector.projector.available = False
                eventprojector.projector.save(update_fields=['available'])
            elif eventprojector.projector.sec.sec_name == 'EC_dept':
                eventprojector.projector.available = False
                eventprojector.projector.save(update_fields=['available'])
            elif eventprojector.projector.sec.sec_name == 'EEE_dept':
                 eventprojector.projector.available = False
                 eventprojector.projector.save(update_fields=['available'])
            elif eventprojector.projector.sec.sec_name == 'IEEE':
                 eventprojector.projector.available = False
                eventprojector.projector.save(update_fields=['available'])
            elif eventprojector.projector.sec.sec_name == 'TCP_dept':
                 eventprojector.projector.available = False
                 eventprojector.projector.save(update_fields=['available'])
return render(request, 'event/projectordetails.html' , {'eventprojector' : eventprojector })