ORM的增刪改查
from django.shortcuts import render
from django.http import HttpResponse
# 從模型中導入這個類
from .models import Book
添加數據
def add_book(request):
"""增加圖書"""
# 添加數據的時候要對應着從模型中導入的類數據字段的一致性
# 實例化對象,並添加數據
book = Book(book_name='利用Python進行數據分析', book_author='Wes Mckinney', book_price=100)
# 寫完之後記得要保存進行保存數據
# save 保存數據
book.save()
return HttpResponse('添加圖書數據成功')
查詢數據
def find_book(request):
"""查詢圖書操作
思路解說:
爲什麼要使用pk,pk其實是primary_key 的單詞縮寫意思
假設我們創建了一個對應的模型,當我們創建的模型的主鍵不叫id了,叫隨便的單詞。
這時候我們在對應的查詢過程中就會出現報錯的情況，如果我們使用pk就不用考慮這點問題，而且還不會報錯
"""
# get:是根據主鍵來進行查詢
# book = Book.objects.get(pk=1)
# print(book)
# 根據其他條件進行查詢
# filter是根據其他條件進行查詢
# book = Book.objects.filter(book_name='Python3網絡爬蟲開發實戰')
# print(book)
# all是查詢除所有的數據
books = Book.objects.all()
for book in books:
print(book)
return HttpResponse('查詢圖書數據成功')
刪除數據
def delete_book(request):
"""對圖書進行刪除操作"""
# 先找到id在進行刪除
book = Book.objects.get(pk=8)
# delete 爲刪除的意思
book.delete()
return HttpResponse('刪除圖書成功')
修改數據
def update_book(request):
"""對圖書進行修改操作"""
book = Book.objects.get(pk=3)
book.book_name = 'Python數據分析'
book.save()
return HttpResponse('更新圖書數據成功')
基於ORM的書籍查詢
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模型來進行操作
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中提供了一個表單驗證,就是csrf_token安全驗證-->
{% csrf_token %}
圖書名字:<input type="text" name="book_name"><br>
圖書作者:<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' %}">首頁</a></li>
<li><a href="#">發佈圖書</a></li>
</ul>
{% block content %}
{% endblock %}
</body>
</html>
book_detail.html
{% extends 'base.html' %}
{% block content %}
<table>
<tr>
<th>序號</th>
<th>圖書名字</th>
<th>圖書作者</th>
<th>操作/刪除</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 %}">刪除圖書</a></td>
</tr>
</table>
{% endblock %}
index.html
{% extends 'base.html' %}
{% block content%}
<ul>
<li><a href="{% url 'front:add_book' %}">添加圖書</a></li>
</ul>
<table>
<tr>
<th>序號</th>
<th>圖書名字</th>
<th>圖書作者</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 %}