在Django中，网页和其他内容是通过视图传递的。每个视图由一个简单的Python函数表示,Django将通过检查请求的URL（准确地说，是域名后面的部分URL）来选择一个视图。
例如，用户在浏览器中访问 <<domain>>/newsarchive/<year>/<month>/ diango的URLConfs 将请求URL与对应的views function 匹配，调用view function 进行数据处理，然后选择对应的template模板进行渲染展示或直接数据返回。
在我们的poll app中，我们将会创建以下四个视图views：
Question “index” page – displays the latest few questions.Question “detail” page – displays a question text, with no results but with a form to vote.Question “results” page – displays results for a particular question.Vote action – handles voting for a particular choice in a particular question.polls/views.py:
from django.http import HttpResponse # Create your views here. def index(request): return HttpResponse("Hello, world. You're at the polls index.") def detail(request, question_id): return HttpResponse("You're looking at question %s." % question_id) def results(request, question_id): response = "You're looking at the results of question %s." return HttpResponse(response % question_id) def vote(request, question_id): return HttpResponse("You're voting on question %s." % question_id)polls/urls.py:
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'), ]URLconfs 中，正则表达式中的分组()作为参数传递给view，如url(r'^(?P<question_id>[0-9]+)/$', views.detail, name='detail')
假如请求url为 polls/34/ 相当于调用detail(request,question_id='34')
分别访问一下url可见调用不同的view 函数进行相应
http://localhost:8000/polls/
http://localhost:8000/polls/34/
http://localhost:8000/polls/34/results/
http://localhost:8000/polls/34/vote/
view的主要工作：获取请求内容，调用数据库model获取数据库数据，调用业务处理Model逻辑处理，将处理结果渲染到指定的模板template中，响应response到客户端浏览器
创建 polls/templates,django会在在app目录下查找templates目录作为模板路径
创建 polls/templates/polls/index.html
Because of how the app_directories template loader works as described above, you can refer to this template within Django simply as polls/index.html.
（当然templates下不创建polls，模板路径调用index.html 也可以，但是强烈不建议这样，因为避免出现不同的app中有相同名称的模板文件时读取区分不出来）
{% 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 %}更新 index view in polls/views.py：
def index(request): latest_question_list = Question.objects.order_by('-pub_date')[:5] context = {'latest_question_list': latest_question_list} return render(request, 'polls/index.html', context)访问 http://localhost:8000/polls/
更新detail view in polls/views.py：
def detail(request, question_id): question = get_object_or_404(Question, pk=question_id) return render(request, 'polls/detail.html', {'question': question})get_object_or_404(),get_list_or_404() 当获取不到对象时，返回404页面
访问 http://localhost:8000/polls/34/
添加 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>django模板系统使用双大括号访问变量属性，如{{question.question_text}},
django模板中，使用 {% %} 将原生pyton语句包含起来，其中以上实例中，使用了for循环：{% for %} {% endfor %}
访问 http://localhost:8000/polls/1
如polls/index.html 中的 <li><a href="/polls/{{ question.id }}/">{{ question.question_text }}</a></li>
修改为：<li><a href="{% url 'detail' question.id %}">{{ question.question_text }}</a></li>
这种URL 查找方式是通过polls.urls 中的name来匹配，如：
mysite/urls.py：
url(r'^polls/', include('polls.urls', namespace="polls")),
polls/urls.py:
# the 'name' value as called by the {% url %} template tagurl(r'^(?P<question_id>[0-9]+)/$', views.detail, name='detail'),
如上例，使用{% url 'detail' %} 可以根据polls.urls 中的name='detail' 来匹配。如果在同一个project下有多个app，其中都有name='detail' 时,又该如何匹配views呢？
解决方法是，添加namespace到URLconf中，如在polls/urls.py 中添加： app_name = 'polls'
则可以在模板中修改{% url 'detail' %} 为 {% url 'polls:detail' %}
访问：http://localhost:8000/polls/
点击“what's up” 链接
转载于:https://www.cnblogs.com/guanfuchang/p/6256685.html
