Django1.10文档学习笔记三

9 django admin站点

D:\workspace_python\mysite>python manage.py createsuperuser

Username (leave blank to use 'administrator'): admin

Email address: [e-mail]

Password:

Password (again):

This password is too short. It must contain at least 8 characters.

This password is too common.

This password is entirely numeric.

Password:yue123456

Password (again):

Superuser created successfully.

重启开发服务器

Python manage.py runserver

http://127.0.0.1/admin

在admin中注册投票应用

Polls/admin.py添加如下内容:

from polls import models

admin.site.register(models.Question)

admin.site.register(models.Choice)

10 编写更多的视图

Poll/views.py,添加如下内容:
'''
问卷详情
'''
def detail(request, question_id):
return HttpResponse('You are looking at question %s.' % question_id)


'''
某个问卷的投票和调查结果
'''
def results(request, question_id):
response = ('You are looking at the results of question %s.')
return HttpResponse(response % question_id)


'''
投票动作页面
'''
def vote(request, question_id):
return HttpResponse('You ar voting on question %s.' % question_id)

Polls/urls.py,添加如下内容:

url(r'^(?P<question_id>[0-9]+)/$',views.detail,name='detail'),
url(r'^(?P<question_id>[0-9]+)/results/$',views.results,name='results'),
url(r'^(?P<question_id>[0-9]+)/vote/$',views.vote,name='vote'),

修改polls/views.py视图

'''
首页
'''
def index(request):
latest_question_list=Question.objects.order_by('-pub_date')[:5]
output=', '.join([q.question_text for q in latest_question_list])
return HttpResponse(output)

在polls目录下创建templates/polls目录,新建index.html,添加如下内容:

{% if latest_question_list %}
<ul>
{% for question in latest_question_list %}
<li>
<a href="/polls/{{ question.id }}/">
{{ question.question_text }}
</a>
</li>
{% endfor %}
</ul>
{% else %}
<p>No polls are available. </p>
{% endif %}

修改视图页面

'''
首页
'''
def index(request):
latest_question_list = Question.objects.order_by('-pub_date')[:5]
template = loader.get_template('polls/index.html')
context = {
'latest_question_list': latest_question_list,
}
return render(request, 'polls/index.html', context)
# return HttpResponse(template.render(context, request))

10 添加404 错误页面

修改polls/views.py

'''
问卷详情
'''
def detail(request, question_id):
#方式一:
try:
question = Question.objects.get(pk=question_id)
except Question.DoesNotExist:
raise Http404("Question does not exist")
return render(request, 'polls/detail.html', {'question': question})
#方式二:
#question = get_object_or_404(Question, pk=question_id)
#return render(request, 'polls/detail.html', {'question': question})

11 使用模板系统

polls/templates/polls/detail.html

<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
<li>{{ choice.choice_text }}</li>
{% endfor %}</ul>
<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
<li>{{ choice.choice_text }}</li>
{% endfor %}
</ul>

12删除模板中硬编码的urls

polls/templates/polls/detail.html

{% if latest_question_list %}
<ul>
{% for question in latest_question_list %}
<li>
{#硬编码#}

<a href="/polls/{{ question.id }}/">
{{ question.question_text }}
</a>
{#可以使用urls.py中定认的别名 #}
<a href="{% url 'detail' question.id %}">
{{ question.question_text }}
</a>
</li>
{% endfor %}
</ul>
{% else %}
<p>No polls are available. </p>
{% endif %}

13 url names的命名空间

Urls.py中添加

app_name='polls'

页面中可以使用

{#可以使用urls.py中定认的命名空间 #}
<a href="{% url 'polls:detail' question.id %}">
{{ question.question_text }}
</a>

14 简单的form表单

<h1>{{ question.question_text }}</h1>

{% if error_message %}
<p>
<strong>{{ error_message }}</strong>
</p>
{% endif %}
<form action="{% url 'polls:vote' question.id %}" method="post">
{% csrf_token %}
{% 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/>
{% endfor %}
<input type="submit" value="Vote"/>
</form>

修改views.py中的vote业务方法

'''
投票动作页面
'''
def vote(request, question_id):
#错误信息页面
question = get_object_or_404(Question, pk=question_id)
try:
#取得投票信息
selected_choice = question.choice_set.get(pk=request.POST['choice'])
except (KeyError, Choice.DoesNotExist):
# 发生choice未找到异常时，重新返回表单页面，并给出提示信息
return render(request, 'polls/detail.html', {'question': question,'error_message': "You didn't select a choice.",})
else:
selected_choice.votes += 1#修改投票数
selected_choice.save()#保存至数据库
# 成功处理数据后，自动跳转到结果页面，防止用户连续多次提交。
return HttpResponseRedirect(reverse('polls:results', args=(question.id,)))

修改results业务方法

'''
某个问卷的投票和调查结果
'''
def results(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, 'polls/results.html', {'question': question})

在polls/templates/polls/results.html

<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
<li>
{{ choice.choice_text }} -- {{ choice.votes }} vote{{ choice.votes|pluralize }}
</li>
{% endfor %}
</ul>
<a href="{% url 'polls:detail' question.id %}">Vote again?</a>

15 使用泛型视图

Polls/urls.p文件内容如下:

from django.conf.urls import url
from . import views

app_name = 'polls'

urlpatterns = [
#url(r'^$', views.index, name='index'),
#url(r'^(?P<question_id>[0-9]+)/$', views.detail, name='detail'),
#url(r'^(?P<question_id>[0-9]+)/results/$', views.results, name='results'),
#使用泛型模板
url(r'^$', views.IndexView.as_view(), name='index'),
url(r'^(?P<pk>[0-9]+)/$', views.DetailView.as_view(), name='detail'),
url(r'^(?P<pk>[0-9]+)/results/$', views.ResultsView.as_view(), name='results'),

url(r'^(?P<question_id>[0-9]+)/vote/$', views.vote, name='vote'),
]

'''
泛型视图
'''
'''
首页
'''
class IndexView(generic.ListView):
template_name = 'polls/index.html'
context_object_name = 'latest_question_list'

#最近的5个调查问卷
def get_queryset(self):
return Question.objects.order_by('-pub_date')[:5]

'''
问卷详情
'''
class DetailView(generic.DetailView):
model = Question
template_name = 'polls/detail.html'

'''
某个问卷的投票和调查结果
'''
class ResultsView(generic.DetailView):
model = Question
template_name = 'polls/results.html'