了解學習pyhton web的簡單demo
1. 安裝Django， 安裝pyhton 自行百度
2. 執行命令創建project django-admin.py startproject mysite
3. 執行命令創建app python manage.py startapp polls
目錄結構： polls/templates/polls 目錄 和 polls/admin.py 都是自己手動創建的。
4. 編輯setting.py 添加app polls 同時打開admin
INSTALLED_APPS = (
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.sites',
'django.contrib.messages',
'django.contrib.staticfiles',
'polls',
# Uncomment the next line to enable the admin:
'django.contrib.admin',
# Uncomment the next line to enable admin documentation:
# 'django.contrib.admindocs',
)
5. 編輯setting.py 添加數據庫連接信息
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
'NAME': 'polls', # Or path to database file if using sqlite3.
'USER': 'root', # Not used with sqlite3.
'PASSWORD': '123', # Not used with sqlite3.
'HOST': '', # Set to empty string for localhost. Not used with sqlite3.
'PORT': '', # Set to empty string for default. Not used with sqlite3.
}
}
6. 創建Modle模型 ：
# coding=utf-8
from django.db import models
# Create your models here.
class Question(models.Model):
question_text = models.CharField(max_length=200)
pub_date = models.DateTimeField('date published')
def __unicode__(self):
return self.question_text
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
7. 執行數據庫同步 （ORM）自動根據model定義創建表接口 （我這里使用的mysql）
首先創建數據庫
create database polls;
然后執行命令：
python manage.py syncdb
8. 檢查數據庫中表的創建：
use polls
show tables
9. 創建admin.py
# coding=utf-8
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)
10. 啟動應用
python manage.py runserver
登錄后台：http://127.0.0.1:8000/admin 通過Django自動的后台進行問題添加
11. 編寫視圖控制層
視圖起着承前啟后的作用，前是指前端頁面，后是指后台數據庫。將數據庫表中的內容查詢出來顯示到頁面上。
編寫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.
# 首頁展示所有問題
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)
# 查看所有問題
def detail(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, 'polls/detail.html', {'question': question})
# 查看投票結果
def results(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, 'polls/results.html', {'question': question})
# 選擇投票
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,)))
12. 配置視圖展示層與邏輯控制層url映射
url是一個請求配置文件，頁面中的請求轉交給由哪個函數處理，由該文件決定。
首先配置polls/urls.py(該文件需要創建)
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，編輯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)),
]
13. 創建視圖模板
模板就是前端頁面，用來將數據顯示到web頁面上。
首先創建polls/templates/polls/目錄，分別在該目錄下創建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>
14. 啟動web容器，訪問：http://127.0.0.1:8000/polls/
