参考官网文档，创建投票系统。
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Windows 7/10
Python 3.6
Django 2.0*
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1、创建项目（mysite）与应用（polls）
D:\pydj>django-admin.py startproject mysite
D:\pydj>cd mysite
D:\pydj\mysite>python manage.py startapp polls
添加到setting.py
# Application definition
INSTALLED_APPS = (
‘django.contrib.admin‘,
‘django.contrib.auth‘,
‘django.contrib.contenttypes‘,
‘django.contrib.sessions‘,
‘django.contrib.messages‘,
‘django.contrib.staticfiles‘,
‘polls‘,
)
最终哪个目录结构：
2、创建模型（即数据库）
一般web开发先设计数据库，数据库设计好了，项目就完了大半了，可见数据库的重要性。打开polls/models.py编写如下：
# coding=utf-8
from django.db import models
# Create your models here.
# 问题
class Question(models.Model):
question_text = models.CharField(max_length=200)
pub_date = models.DateTimeField(‘date published‘)
def __unicode__(self):
return self.question_text
# 选择
class Choice(models.Model):
question = models.ForeignKey(Question)
choice_text = models.CharField(max_length=200)
votes = models.IntegerField(default=0)
def __unicode__(self):
return self.choice_text
执行数据库表生成与同步。
D:\pydj\mysite>python manage.py makemigrations polls
Migrations for ‘polls‘:
0001_initial.py:
- Create model Question
- Create model Choice
- Add field question to choice
D:\pydj\mysite>python manage.py syncdb（1.9后：python manage.py migrate）
……
You have installed Django‘s auth system, and don‘t have any superusers defined.
Would you like to create one now? (yes/no): yes
Username (leave blank to use ‘fnngj‘): 用户名（默认当前系统用户名）
Email address: [email protected] 邮箱地址
Password: 密码
Password (again): 重复密码
Superuser created successfully.
【1.9版本后】
Operations to perform:
Apply all migrations: admin, auth, contenttypes, polls, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying auth.0009_alter_user_last_name_max_length... OK
Applying polls.0001_initial... OK
Applying sessions.0001_initial... OK
D:\pydj\mysite>python manage.py createsuperuser(1.9版本后创建超级用户)
Username (leave blank to use ‘liwei15515‘): root
Email address: [email protected]
Password:
Password (again):
Superuser created successfully.
3、admin管理
django提供了强大的后台管理，对于web应用来说，后台必不可少，例如，当前投票系统，如何添加问题与问题选项？直接操作数据库添加，显然麻烦，不方便，也不安全。所以，管理后台就可以完成这样的工作。
打开polls/admin.py文件，编写如下内容：
from django.contrib import admin
from .models import Question, Choice
# Register your models here.
class ChoiceInline(admin.TabularInline):
model = Choice
extra = 3
class QuestionAdmin(admin.ModelAdmin):
fieldsets = [
(None, {‘fields‘: [‘question_text‘]}),
(‘Date information‘, {‘fields‘: [‘pub_date‘], ‘classes‘: [‘collapse‘]}),
]
inlines = [ChoiceInline]
list_display = (‘question_text‘, ‘pub_date‘)
admin.site.register(Choice)
admin.site.register(Question, QuestionAdmin)
当前脚本的作用就是将模型（数据库表）交由admin后台管理。
运行web容器：
D:\pydj\mysite>python manage.py runserver Performing system checks... System check identified no issues (0 silenced). October 05, 2015 - 13:08:12 Django version 1.8.2, using settings ‘mysite.settings‘ Starting development server at http://127.0.0.1:8000/ Quit the server with CTRL-BREAK.
登录后台：http://127.0.0.1:8000/admin
登录密码就是在执行数据库同步时设置的用户名和密码。
点击“add”添加问题。
4、编写视图
视图起着承前启后的作用，前是指前端页面，后是指后台数据库。将数据库表中的内容查询出来显示到页面上。
编写polls/views.py文件：
# coding=utf-8
from django.shortcuts import render, get_object_or_404
from django.http import HttpResponseRedirect, HttpResponse
from django.core.urlresolvers import reverse
from .models import Question, Choice
# Create your views here.
# 首页展示所有问题
def index(request):
# latest_question_list2 = Question.objects.order_by(‘-pub_data‘)[:2]
latest_question_list = Question.objects.all()
context = {‘latest_question_list‘: latest_question_list}
return render(request, ‘polls/index.html‘, context)
# 查看所有问题
def detail(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, ‘polls/detail.html‘, {‘question‘: question})
# 查看投票结果
def results(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, ‘polls/results.html‘, {‘question‘: question})
# 选择投票
def vote(request, question_id):
p = get_object_or_404(Question, pk=question_id)
try:
selected_choice = p.choice_set.get(pk=request.POST[‘choice‘])
except (KeyError, Choice.DoesNotExist):
# Redisplay the question voting form.
return render(request, ‘polls/detail.html‘, {
‘question‘: p,
‘error_message‘: "You didn‘t select a choice.",
})
else:
selected_choice.votes += 1
selected_choice.save()
# Always return an HttpResponseRedirect after successfully dealing
# with POST data. This prevents data from being posted twice if a
# user hits the Back button.
return HttpResponseRedirect(reverse(‘polls:results‘, args=(p.id,)))
5、配置url
url是一个请求配置文件，页面中的请求转交给由哪个函数处理，由该文件决定。
首先配置polls/urls.py(该文件需要创建)
from django.conf.urls import url
from . import views
urlpatterns = [
# ex : /polls/
url(r‘^$‘, views.index, name=‘index‘),
# ex : /polls/5/
url(r‘^(?P<question_id>[0-9]+)/$‘, views.detail, name=‘detail‘),
# ex : /polls/5/results/
url(r‘^(?P<question_id>[0-9]+)/results/$‘, views.results, name=‘results‘),
# ex : /polls/5/vote
url(r‘^(?P<question_id>[0-9]+)/vote/$‘, views.vote, name=‘vote‘),
]
接着，编辑mysite/urls.py文件。
from django.conf.urls import include, url
from django.contrib import admin
urlpatterns = [
url(r‘^polls/‘, include(‘polls.urls‘, namespace="polls")),
url(r‘^admin/‘, include(admin.site.urls)),
]
6、创建模板
模板就是前端页面，用来将数据显示到web页面上。
首先创建polls/templates/polls/目录，分别在该目录下创建index.html、detail.html和results.html文件。
index.html
{% if latest_question_list %}
<ul>
{% for question in latest_question_list %}
<li><a href="{% url ‘polls:detail‘ question.id %}">{{ question.question_text }}</a></li>
{% endfor %}
</ul>
{% else %}
<p>No polls are available.</p>
{% endif %}
detail.html
<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>
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>
7、功能展示
启动web容器，访问：http://127.0.0.1:8000/polls/
原文地址：https://www.cnblogs.com/deepminer/p/9144420.html