Django(四)-搭建第一个应用(3)
一、问题详情页
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>展示某个投票的问题和不带结果的选项列表</title>
</head>
<body><form action="{% url 'polls:vote' question.id %}" method="post">
{% csrf_token %}
<fieldset><legend><h1>{{ question.question_text }}</h1></legend>{% if error_message %}<p><strong> {{ error_message }}</strong> </p> {% endif %}{% for choice in question.choice_set.all %}<input type="radio" name="choice" id="choice{{ forloop.counter }}" value="{{ choice.id }}"><label for="choice{{ forloop.counter }}">{{ choice.choice_text }}</label><br><li>{{ choice.choice_text }}</li>{% endfor %}
</fieldset>
<input type="submit" value="Vote">
</form>
</body>
</html>二、问题结果页
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body>
<h1> {{ question.question_text }}</h1>
<ul>{% for choice in question.choice_set.all %}<li> {{ choice.choice_test }} -- {{ choice.votes }}</li>{% endfor %}
</ul>{# 跳转到某一问题的投票详情页#}
<a href="{% url 'polls:detail' question.id %}">vote again?</a></body>
</html>三、投票处理器视图
# 3.投票处理器：用于响应用户为某个问题的特定选项投票的操作
def vote(request,question_id):question = get_object_or_404(Question,pk = question_id)try:selected_choice = question.choice_set.get(pk = request.POST["choice"])except (KeyError,Choice.DoesNotExist):return render(request,"polls/detail.html",{"quesiton":question,"error_message":"You didn't select a choice"})else:selected_choice.votes = F("votes") + 1selected_choice.save()return HttpResponseRedirect(reverse("polls:results",args=(question.id,)))
四、引入通用视图之前的urlCONF
from django.urls import pathfrom . import views# 为视图函数配置url
# name
# 设置app的命名空间,主要是为了区分不同app下相同名字的视图
app_name = "polls"
urlpatterns = [# 当 Django 响应一个请求时，它会从 urlpatterns 的第一项开始，按顺序依次匹配列表中的项，直到找到匹配的项。# 比如URLconf 在处理请求 https://www.example.com/myapp/ 时，它会尝试匹配 myapp/path("",views.index,name= "index"),path("<int:question_id>/",views.detail,name = "detail"),path("<int:question_id>/results/", views.results, name = "results"),path("<int:question_id>/vote/", views.vote, name = "vote"),
]五、引入通用视图
from django.db.models import F
from django.http import HttpResponse, Http404,HttpResponseRedirect
from django.shortcuts import render, get_object_or_404
from django.urls import reverse
from django.views.generic import ListView
from django.views import generic# Create your views here.from .models import Question,Choiceclass indexView(generic.ListView):# 默认情况下，ListView使用一个叫做 <app name>/<model name>_list.html的默认模板# 因此默认模板为polls/index_list.html# 此例我本手动指定template_name为"polls/index.html"template_name = "polls/index.html"# 默认的上下文变量名(其对应的值会传递到index.html)为question_list(命名规则:模板名小写_list)# 因为之前的代码中,在index.html中引用的变量名都是latest_question_list,因此使用context_object_name覆盖默认的行为context_object_name = "latest_question_list"# 如果不重写get_queryset,而使用默认的 model = Question# 其实等价于 Question.objects.all()def get_queryset(self):"""返回最近5个发布的问题"""return Question.objects.order_by("-pub_date")[:5]# latest_question_list = Question.objects.order_by("-pub_date")[:5]# context = {"latest_question_list":latest_question_list}# return render(request,"polls/index.html",context)# output = ", ".join([q.question_text for q in latest_question_list])# return HttpResponse(output)# 1.问题详情页：展示某个投票的问题和不带结果的选项列表
class detailView(generic.DetailView):model = Questiontemplate_name = "polls/detail.html"# 404异常处理-传统方式# try:# question = Question.objects.get(pk=question_id)# except Question.DoesNotExist:# raise Http404("Quesition does not exit")# 404异常处理-利用Django提供的函数# question = get_object_or_404(Question,pk=question_id)# return render(request,"polls/detail.html",{"question":question})# 2.问题结果页：展示某个投票的结果
class resultsView(generic.DetailView):model = Questiontemplate_name = "polls/result.html"# question = get_object_or_404(Question,pk= question_id)# return render(request,"polls/result.html",{"question":question})# 3.投票处理器：用于响应用户为某个问题的特定选项投票的操作
def vote(request,question_id):question = get_object_or_404(Question,pk = question_id)try:selected_choice = question.choice_set.get(pk = request.POST["choice"])except (KeyError,Choice.DoesNotExist):return render(request,"polls/detail.html",{"quesiton":question,"error_message":"You didn't select a choice"})else:selected_choice.votes = F("votes") + 1selected_choice.save()return HttpResponseRedirect(reverse("polls:results",args=(question.id,)))六、引入通用视图之后的urlCONF
第二和第三个模式的路径字符串中匹配的模式名称已从 <question_id> 更改为 <pk>。这是因为我们将使用 DetailView 通用视图来替换我们的 detail() 和 results() 视图，它期望从 URL 中捕获的主键值被称为 "pk"。
from django.urls import pathfrom . import views# 为视图函数配置url
# name
# 设置app的命名空间,主要是为了区分不同app下相同名字的视图
app_name = "polls"
urlpatterns = [# 当 Django 响应一个请求时，它会从 urlpatterns 的第一项开始，按顺序依次匹配列表中的项，直到找到匹配的项。# 比如URLconf 在处理请求 https://www.example.com/myapp/ 时，它会尝试匹配 myapp/path("",views.indexView.as_view(),name= "index"),path("<int:pk>/",views.detailView.as_view(),name = "detail"),path("<int:pk>/results/", views.resultsView.as_view(), name = "results"),path("<int:question_id>/vote/", views.vote, name = "vote"),
]