创建项目

Django 命令

  1. (learnDjango) ~\> django-admin
  3. Type 'django-admin help <subcommand>' for help on a specific subcommand.
  5. Available subcommands:
  7. [django]
  8.     check
  9.     compilemessages
  10.     createcachetable
  11.     dbshell
  12.     diffsettings
  13.     dumpdata
  14.     flush
  15.     inspectdb
  16.     loaddata
  17.     makemessages
  18.     makemigrations
  19.     migrate
  20.     runserver
  21.     sendtestemail
  22.     shell
  23.     showmigrations
  24.     sqlflush
  25.     sqlmigrate
  26.     sqlsequencereset
  27.     squashmigrations
  28.     startapp
  29.     startproject
  30.     test
  31.     testserver
  32. Note that only Django core commands are listed as settings are not properly configured (error: Requested setting INSTALLED_APPS, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE
  33.  or call settings.configure() before accessing settings.).

创建一个项目并尝试运行

  1. django-admin startproject demo
  2. cd demo
  3. python manage.py runserver

创建管理员用户

  1. python manage.py migrate
  2. python .\manage.py createsuperuser

运行项目

  1. # http://127.0.0.1:8000/
  2. python manage.py runserver
  3. # http://127.0.0.1:8080/
  4. python manage.py runserver 8080
  5. # http://ip:8000/ 可以从外部访问
  6. python manage.py runserver 0:8000

Hello world!

创建应用

  1. python manage.py startapp helloworld

编辑 settings.py ，添加如下代码

  1. INSTALLED_APPS = [
  2.     'helloworld.apps.HelloworldConfig',
  3. ]

编辑 helloworld/templates/helloworld/index.html 

  1. <!DOCTYPE html>
  2. <html lang="zh">
  3. <head>
  4.     <meta charset="UTF-8">
  5.     <title>Hello world!</title>
  6. </head>
  7. <body>
  8. <h1>{{ text }}</h1>
  9. </body>
  10. </html>

编辑 helloworld/views.py

  1. from django.shortcuts import render
  3. def index(request):
  4.     return render(request, 'helloworld/index.html', {'text': "Hello world!"})

编辑 helloworld/urls.py 

  1. from django.urls import path
  3. from . import views
  5. urlpatterns = [
  6.     path('', views.index, name='index'),
  7. ]

编辑 urls.py 

  1. from django.contrib import admin
  2. from django.urls import include, path
  4. urlpatterns = [
  5.     path('helloworld/', include('helloworld.urls')),
  6. ]

编写一个投票应用

创建应用

  1. python manage.py startapp polls

编辑 settings.py ，添加如下代码

  1. INSTALLED_APPS = [
  2.     'polls.apps.PollsConfig',
  3. ]

定义模型

编辑 polls/models.py ，定义模型并创建表结构

  1. from django.db import models
  3. # 话题
  4. class Topic(models.Model):
  5.     topic_text = models.CharField(max_length=200)
  6.     topic_date = models.DateTimeField('date published')
  8.     # 返回对象描述信息
  9.     def __str__(self):
  10.         return self.topic_text
  12. # 投票选项
  13. class Choice(models.Model):
  14.     topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
  15.     choice_text = models.CharField(max_length=200)
  16.     choice_count = models.IntegerField(default=0)
  18.     # 返回对象描述信息
  19.     def __str__(self):
  20.         return self.choice_text
  1. # 让 Django 知道模型变更
  2. python manage.py makemigrations polls
  3. # 创建表结构
  4. python manage.py migrate polls

编辑模板

编辑 index.html

  1. <!DOCTYPE html>
  2. <html lang="zh">
  3. <head>
  4.     <meta charset="UTF-8">
  5.     <title>polls</title>
  6.     {% load static %}
  7.     <link rel="stylesheet" type="text/css" href="{% static 'polls/style.css' %}">
  8. </head>
  9. <body>
  10. {#显示话题列表#}
  11. {% if latest_topic_list %}
  12.     <ul>
  13.         {% for topic in latest_topic_list %}
  14.             <li><a href="{% url 'polls:detail' topic.id %}">{{ topic.topic_text }}</a></li>
  15.         {% endfor %}
  16.     </ul>
  17. {% else %}
  18.     <p>话题列表为空！</p>
  19. {% endif %}
  20. </body>
  21. </html>

编辑 detail.html

  1. <!DOCTYPE html>
  2. <html lang="zh">
  3. <head>
  4.     <meta charset="UTF-8">
  5.     <title>detail</title>
  6. </head>
  7. <body>
  8. {#话题内容#}
  9. <p>{{ topic.topic_text }}</p>
  11. {#错误信息#}
  12. {% if error_message %} <p><strong>{{ error_message }}</strong></p>  {% endif %}
  14. {#表单部分#}
  15. <form action="{% url 'polls:vote' topic.id %}" method="post">
  16.     {% csrf_token %}
  17.     {% for choice in topic.choice_set.all %}
  18.         <input type="radio" name="choice" id="choice{{ forloop.counter }}" value="{{ choice.id }}">
  19.         <label for="choice{{ forloop.counter }}">{{ choice.choice_text }}</label>
  20.         <br>
  21.     {% endfor %}
  22.     <br>
  23.     <input type="submit" value="Vote">
  24. </form>
  25. </body>
  26. </html>

编辑 result.html

  1. <!DOCTYPE html>
  2. <html lang="zh">
  3. <head>
  4.     <meta charset="UTF-8">
  5.     <title>results</title>
  6. </head>
  7. <body>
  8. {#话题内容#}
  9. <p>{{ topic.topic_text }}</p>
  11. {#投票结果#}
  12. <table border="1">
  13.     {% for choice in topic.choice_set.all %}
  14.     <tr>
  15.         <td>{{ choice.choice_text }}</td>
  16.         <td>{{ choice.choice_count }}</td>
  17.     </tr>
  18.     {% endfor %}
  19. </table>
  20. <br>
  22. {#再次投票#}
  23. <a href="{% url 'polls:detail' topic.id %}">再次投票</a>
  24. </body>
  25. </html>

编辑视图

编辑 polls/views.py

  1. from django.shortcuts import render, get_object_or_404
  2. from django.http import HttpResponseRedirect
  3. from django.urls import reverse
  4. from django.views import generic
  5. from django.utils import timezone
  7. from .models import Topic, Choice
  9. # 主页视图
  10. class IndexView(generic.ListView):
  11.     template_name = 'polls/index.html'
  12.     context_object_name = 'latest_topic_list'
  14.     def get_queryset(self):
  15.         return Topic.objects.filter(
  16.             topic_date__lte=timezone.now()
  17.         ).order_by('-topic_date')[:5]
  19. # 话题详情页视图
  20. class DetailView(generic.DetailView):
  21.     model = Topic
  22.     template_name = 'polls/detail.html'
  24. # 投票结果视图
  25. class ResultsView(generic.DetailView):
  26.     model = Topic
  27.     template_name = 'polls/result.html'
  29. # 投票
  30. def vote(request, topic_id):
  31.     topic = get_object_or_404(Topic, pk=topic_id)
  32.     try:
  33.         choice_selected = topic.choice_set.get(pk=request.POST['choice'])
  34.     except (KeyError, Choice.DoesNotExist):
  35.         return render(request, 'polls/detail.html', {
  36.             'topic': topic,
  37.             'error_message': "你没有选择一个选项！",
  38.         })
  39.     else:
  40.         choice_selected.choice_count += 1
  41.         choice_selected.save()
  42.         # 重定向到 result 页面
  43.         return HttpResponseRedirect(reverse('polls:result', args=(topic.id,)))

编辑路由

编辑路由 polls/urls.py

  1. from django.urls import path
  3. from . import views
  5. app_name = 'polls'
  6. urlpatterns = [
  7.     # ex: /polls/
  8.     path('', views.IndexView.as_view(), name='index'),
  9.     # ex: /polls/5/
  10.     path('<int:pk>/', views.DetailView.as_view(), name='detail'),
  11.     # ex: /polls/5/results/
  12.     path('<int:pk>/result/', views.ResultsView.as_view(), name='result'),
  13.     # ex: /polls/5/vote/
  14.     path('<int:question_id>/vote/', views.vote, name='vote'),
  15. ]

编辑全局路由 urls.py

  1. from django.contrib import admin
  2. from django.urls import include, path
  4. urlpatterns = [
  5.     path('polls/', include('polls.urls')),
  6. ]