ORM的增删改查
from django.shortcuts import render
from django.http import HttpResponse
# 从模型中导入这个类
from .models import Book
添加数据
def add_book(request):
"""增加图书"""
# 添加数据的时候要对应着从模型中导入的类数据字段的一致性
# 实例化对象,并添加数据
book = Book(book_name='利用Python进行数据分析', book_author='Wes Mckinney', book_price=100)
# 写完之后记得要保存进行保存数据
# save 保存数据
book.save()
return HttpResponse('添加图书数据成功')
查询数据
def find_book(request):
"""查询图书操作
思路解说:
为什么要使用pk,pk其实是primary_key 的单词缩写意思
假设我们创建了一个对应的模型,当我们创建的模型的主键不叫id了,叫随便的单词。
这时候我们在对应的查询过程中就会出现报错的情况，如果我们使用pk就不用考虑这点问题，而且还不会报错
"""
# get:是根据主键来进行查询
# book = Book.objects.get(pk=1)
# print(book)
# 根据其他条件进行查询
# filter是根据其他条件进行查询
# book = Book.objects.filter(book_name='Python3网络爬虫开发实战')
# print(book)
# all是查询除所有的数据
books = Book.objects.all()
for book in books:
print(book)
return HttpResponse('查询图书数据成功')
删除数据
def delete_book(request):
"""对图书进行删除操作"""
# 先找到id在进行删除
book = Book.objects.get(pk=8)
# delete 为删除的意思
book.delete()
return HttpResponse('删除图书成功')
修改数据
def update_book(request):
"""对图书进行修改操作"""
book = Book.objects.get(pk=3)
book.book_name = 'Python数据分析'
book.save()
return HttpResponse('更新图书数据成功')
基于ORM的书籍查询
front/views.py
from django.shortcuts import render, redirect, reverse
from django.http import HttpResponse
from .models import Book
# Create your views here.
def index(request):
# 使用ORM模型来进行操作
books = Book.objects.all()
context = {
'books': books
}
return render(request, 'index.html', context=context)
def add_book(request):
if request.method == 'POST':
name = request.POST.get('book_name')
author = request.POST.get('book_author')
book = Book(book_name=name, author=author)
book.save()
return redirect(reverse('front:index'))
else:
return render(request, 'add_book.html')
def book_detail(request, book_id):
book = Book.objects.get(pk=book_id)
content = {
'book': book
}
return render(request, 'book_detail.html', context=content)
def book_delete(request, book_id):
if book_id:
book = Book.objects.get(pk=book_id)
book.delete()
return redirect(reverse('front:index'))
else:
return render(request, 'book_delete.html')
front/urls.py
# @Time : 2020/6/28 14:14
# @Author : SmallJ
from . import views
from django.urls import path
app_name = 'front'
urlpatterns = [
path("", views.index, name='index'),
path("add_book/", views.add_book, name='add_book'),
path("book_detail/<int:book_id>/", views.book_detail, name='book_detail'),
path('book_delete/<int:book_id>/', views.book_delete, name='book_delete')
]
add_book.html
{% extends 'base.html' %}
{% block content %}
<form action="" method="post">
<!-- 在Django中提供了一个表单验证,就是csrf_token安全验证-->
{% csrf_token %}
图书名字:<input type="text" name="book_name"><br>
图书作者:<input type="text" name="book_author"><br>
<input type="submit" value="提交">
</form>
{% endblock %}
base.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<ul>
<li><a href="{% url 'front:index' %}">首页</a></li>
<li><a href="#">发布图书</a></li>
</ul>
{% block content %}
{% endblock %}
</body>
</html>
book_detail.html
{% extends 'base.html' %}
{% block content %}
<table>
<tr>
<th>序号</th>
<th>图书名字</th>
<th>图书作者</th>
<th>操作/删除</th>
</tr>
<tr>
<td>{{ book.pk }}</td>
<td>{{ book.book_name }}</td>
<td>{{ book.author }}</td>
<td><a href="{% url 'front:book_delete' book_id=book.pk %}">删除图书</a></td>
</tr>
</table>
{% endblock %}
index.html
{% extends 'base.html' %}
{% block content%}
<ul>
<li><a href="{% url 'front:add_book' %}">添加图书</a></li>
</ul>
<table>
<tr>
<th>序号</th>
<th>图书名字</th>
<th>图书作者</th>
</tr>
{% for book in books %}
<tr>
<td>{{ forloop.counter }}</td>
<td><a href="{% url 'front:book_detail' book_id=book.id %}">{{ book.book_name }}</a></td>
<td>{{ book.author }}</td>
</tr>
{% endfor %}
</table>
{% endblock %}