Python从入门到实践project Web 应⽤程序 Django ⼊门.2

project Web 应⽤程序

Django ⼊门

1.创建网页：学习笔记主页

2.创建其他网页

创建网页：学习笔记主页

映射 URL

from django.urls import path, include

path('', include('learning_logs.urls')),

"""定义 learning_logs 的 URL 模式"""
from django.urls import path
from . import views

app_name = 'learning_logs'
urlpatterns = [
# 主⻚
path('', views.index, name='index'),
 ]

编写视图

def index(request):
    # 添加为主⻚编写视图的代码
    """学习笔记的主⻚"""
    return render(request, 'learning_logs/index.html')

编写模板

<p>Learning Log</p>
<p>Learning Log helps you keep track of your learning, for any topic
you're
interested in.</p>

创建其他⽹⻚

模板继承

01. ⽗模板

<p>
<a href="{% url 'learning_logs:index' %}">Learning Log</a>
 </p>
{% block content %}{% endblock content %}

02. ⼦模板

{% extends 'learning_logs/base.html' %}
 {% block content %}
<p>Learning Log helps you keep track of your learning, for any topic
you're
interested in.</p>
 {% endblock content %}

显⽰所有主题的⻚⾯

01. URL 模式

# 显⽰所有主题的页面
path('topics/', views.topics, name='topics'),

02. 视图

from .models import Topic

def topics(request):
    """显⽰所有的主题"""
    topics = Topic.objects.order_by('date_added')    # 查询数据库：请求提供 Topic 对象，并根据属性 date_added 进⾏排序
    context = {'topics': topics}   # 定义⼀个将发送给模板的上下⽂，上下⽂（context）是⼀个字典
    return render(request, 'learning_logs/topics.html', context)

03. 模板

 {% extends 'learning_logs/base.html' %}

 {% block content %}

    <p>Topics</p>

     <ul>
        {% for topic in topics %}
            <li>{{ topic.text }}</li>
        {% empty %}
             <li>No topics have been added yet.</li>
        {% endfor %}
     </ul>

 {% endblock content %}

<a href="{% url 'learning_logs:index' %}">Learning Log</a> -
<a href="{% url 'learning_logs:topics' %}">Topics</a>

显⽰特定主题的⻚⾯

01. URL 模式

# 特定主题的详细⻚⾯
path('topics/<int:topic_id>/', views.topic, name='topic'),

02. 视图

def topic(request, topic_id):
    """显⽰单个主题及其所有的条⽬"""
    topic = Topic.objects.get(id=topic_id)
    entries = topic.entry_set.order_by('-date_added')
    context = {'topic': topic, 'entries': entries}
    return render(request, 'learning_logs/topic.html', context)

03. 模板

{% extends 'learning_logs/base.html' %}

{% block content %}

   <p>Topic: {{ topic.text }}</p>
   <p>Entries:</p>
    <ul>
       {% for entry in entries %}
           <li>
               <p>{{ entry.date_added|date:'M d, Y H:i' }}</p>
               <p>{{ entry.text|linebreaks }}</p>
           </li>
       {% empty %}
            <li>There are no entries for this topic yet.</li>
       {% endfor %}
    </ul>

{% endblock content %}

04. 将显⽰所有主题的⻚⾯中的每个主题都设置为链接

 {% extends 'learning_logs/base.html' %}

 {% block content %}

    <p>Topic: {{ topic.text }}</p>
    <p>Entries:</p>
     <ul>
        {% for topic in topics %}
            <li>
               <a href="{% url 'learning_logs:topic' topic.id %}">
                   {{ topic.text }}</a>
            </li>
        {% empty %}
             <li>No topics have been added yet.</li>
        {% endfor %}

        {% for entry in entries %}
            <li>
                <p>{{ entry.date_added|date:'M d, Y H:i' }}</p>
                <p>{{ entry.text|linebreaks }}</p>
            </li>
        {% empty %}
            <li>There are no entries for this topic yet.</li>
        {% endfor %}
     </ul>

 {% endblock content %}