每天40分玩转Django：Django类视图

Django类视图

一、知识要点概览表

类别	知识点	掌握程度要求
基础视图	View、TemplateView、RedirectView	深入理解
通用显示视图	ListView、DetailView	熟练应用
通用编辑视图	CreateView、UpdateView、DeleteView	熟练应用
Mixin机制	ContextMixin、LoginRequiredMixin	理解原理
视图配置	URL配置、参数传递、模板指定	熟练应用

二、基础视图实现

1. 基本View类

# views.py
from django.views import View
from django.http import HttpResponse
from django.shortcuts import renderclass HelloView(View):def get(self, request, *args, **kwargs):return HttpResponse("Hello, Class-based Views!")def post(self, request, *args, **kwargs):return HttpResponse("POST request received")class DashboardView(View):template_name = 'dashboard.html'def get(self, request):context = {'username': request.user.username,'page_title': 'Dashboard'}return render(request, self.template_name, context)

2. TemplateView使用

# views.py
from django.views.generic import TemplateViewclass HomePageView(TemplateView):template_name = "home.html"def get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)context['page_title'] = '首页'context['features'] = ['基于类的视图','通用视图','Mixin机制']return context

3. RedirectView示例

# views.py
from django.views.generic import RedirectViewclass GitHubRedirectView(RedirectView):url = 'https://github.com'permanent = False  # 使用302临时重定向query_string = True  # 保留查询字符串class OldPostRedirectView(RedirectView):permanent = True  # 使用301永久重定向def get_redirect_url(self, *args, **kwargs):post_id = kwargs['post_id']return f'/blog/posts/{post_id}/'

三、通用显示视图

1. ListView实现

# models.py
from django.db import modelsclass Article(models.Model):title = models.CharField(max_length=200)content = models.TextField()created_at = models.DateTimeField(auto_now_add=True)updated_at = models.DateTimeField(auto_now=True)is_published = models.BooleanField(default=False)def __str__(self):return self.title# views.py
from django.views.generic import ListView
from .models import Articleclass ArticleListView(ListView):model = Articletemplate_name = 'articles/article_list.html'context_object_name = 'articles'paginate_by = 10def get_queryset(self):"""只显示已发布的文章"""return Article.objects.filter(is_published=True).order_by('-created_at')def get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)context['total_articles'] = self.get_queryset().count()return context

2. DetailView实现

# views.py
from django.views.generic import DetailView
from django.shortcuts import get_object_or_404class ArticleDetailView(DetailView):model = Articletemplate_name = 'articles/article_detail.html'context_object_name = 'article'def get_object(self, queryset=None):"""自定义获取对象的方法"""obj = super().get_object(queryset=queryset)# 增加访问次数obj.views_count = obj.views_count + 1obj.save()return objdef get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)# 添加相关文章context['related_articles'] = Article.objects.filter(is_published=True).exclude(id=self.object.id)[:3]return context

四、通用编辑视图

1. CreateView实现

# forms.py
from django import forms
from .models import Articleclass ArticleForm(forms.ModelForm):class Meta:model = Articlefields = ['title', 'content', 'is_published']def clean_title(self):title = self.cleaned_data['title']if len(title) < 5:raise forms.ValidationError("标题长度不能少于5个字符")return title# views.py
from django.views.generic.edit import CreateView
from django.urls import reverse_lazy
from .forms import ArticleFormclass ArticleCreateView(CreateView):model = Articleform_class = ArticleFormtemplate_name = 'articles/article_form.html'success_url = reverse_lazy('article_list')def form_valid(self, form):"""表单验证成功时的处理"""form.instance.author = self.request.userresponse = super().form_valid(form)# 可以在这里添加额外的处理逻辑return responsedef get_initial(self):"""设置表单初始值"""return {'title': '新文章','is_published': False}

2. UpdateView实现

# views.py
from django.views.generic.edit import UpdateView
from django.contrib.auth.mixins import LoginRequiredMixinclass ArticleUpdateView(LoginRequiredMixin, UpdateView):model = Articleform_class = ArticleFormtemplate_name = 'articles/article_update.html'def get_success_url(self):return reverse_lazy('article_detail',kwargs={'pk': self.object.pk})def get_queryset(self):"""确保用户只能编辑自己的文章"""return Article.objects.filter(author=self.request.user)

3. DeleteView实现

# views.py
from django.views.generic.edit import DeleteView
from django.urls import reverse_lazy
from django.contrib.auth.mixins import UserPassesTestMixinclass ArticleDeleteView(LoginRequiredMixin, UserPassesTestMixin, DeleteView):model = Articletemplate_name = 'articles/article_confirm_delete.html'success_url = reverse_lazy('article_list')def test_func(self):"""检查用户是否有权限删除文章"""article = self.get_object()return self.request.user == article.authordef delete(self, request, *args, **kwargs):"""自定义删除逻辑"""self.object = self.get_object()success_url = self.get_success_url()# 可以在这里添加其他清理工作self.object.delete()return HttpResponseRedirect(success_url)

五、类视图的URL配置

# urls.py
from django.urls import path
from . import viewsapp_name = 'articles'urlpatterns = [path('', views.ArticleListView.as_view(), name='article_list'),path('<int:pk>/', views.ArticleDetailView.as_view(), name='article_detail'),path('create/', views.ArticleCreateView.as_view(), name='article_create'),path('<int:pk>/update/', views.ArticleUpdateView.as_view(), name='article_update'),path('<int:pk>/delete/', views.ArticleDeleteView.as_view(), name='article_delete'),
]

六、类视图执行流程图

在这里插入图片描述

七、Mixin的使用

1. 自定义Mixin

class TitleMixin:title = ''def get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)context['title'] = self.titlereturn contextclass AuthorRequiredMixin:"""确保用户是作者的Mixin"""def dispatch(self, request, *args, **kwargs):obj = self.get_object()if obj.author != request.user:raise PermissionDeniedreturn super().dispatch(request, *args, **kwargs)class PageTitleMixin:page_title = ''def get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)context['page_title'] = self.page_titlereturn context# 使用Mixin
class ArticleDetailView(TitleMixin, PageTitleMixin, DetailView):model = Articletemplate_name = 'articles/article_detail.html'title = '文章详情'page_title = '查看文章'

2. 常用Mixin组合

from django.contrib.auth.mixins import (LoginRequiredMixin,PermissionRequiredMixin
)class ArticleAdminView(LoginRequiredMixin,PermissionRequiredMixin,ListView
):model = Articletemplate_name = 'articles/admin_list.html'permission_required = 'articles.view_article'def get_queryset(self):return Article.objects.all().order_by('-created_at')class StaffRequiredMixin(UserPassesTestMixin):def test_func(self):return self.request.user.is_staffclass ArticleStaffView(StaffRequiredMixin, ListView):model = Articletemplate_name = 'articles/staff_list.html'

八、模板示例

<!-- templates/articles/article_list.html -->
{% extends 'base.html' %}{% block content %}
<div class="container"><h1>{{ page_title }}</h1><div class="article-list">{% for article in articles %}<div class="article-item"><h2>{{ article.title }}</h2><p>{{ article.content|truncatewords:30 }}</p><div class="article-meta"><span>作者: {{ article.author }}</span><span>发布时间: {{ article.created_at|date:"Y-m-d" }}</span></div><div class="article-actions"><a href="{% url 'articles:article_detail' article.pk %}"class="btn btn-primary">查看详情</a>{% if user == article.author %}<a href="{% url 'articles:article_update' article.pk %}"class="btn btn-secondary">编辑</a><a href="{% url 'articles:article_delete' article.pk %}"class="btn btn-danger">删除</a>{% endif %}</div></div>{% empty %}<p>暂无文章</p>{% endfor %}</div>{% if is_paginated %}<nav aria-label="Page navigation"><ul class="pagination">{% if page_obj.has_previous %}<li class="page-item"><a class="page-link" href="?page={{ page_obj.previous_page_number }}">上一页</a></li>{% endif %}{% for num in page_obj.paginator.page_range %}<li class="page-item {% if page_obj.number == num %}active{% endif %}"><a class="page-link" href="?page={{ num }}">{{ num }}</a></li>{% endfor %}{% if page_obj.has_next %}<li class="page-item"><a class="page-link" href="?page={{ page_obj.next_page_number }}">下一页</a></li>{% endif %}</ul></nav>{% endif %}
</div>
{% endblock %}