Django之批量插入数据以及分页
批量插入数据
l = []
for i in range(10000):
l.append(models.Book2(name='第%s本书'%i))
models.Book2.objects.bulk_create(l) # 批量插入数据
urls.py
rom django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
url(r'^booklist/', views.book_list),
]
views.py
from app01 import models
def book_list(request):
# 动态插入100000条数据
l=[]
for i in range(10000):
l.append(models.Book2(name="第%s本书"%i))
models.Book2.objects.bulk_create(l)
# 查询所有的书籍展示到前端页面
book_list=models.Book2.objects.all()
return render(request,'booklist.html',locals())
models.py
from django.db import models
class Book2(models.Model):
name=models.CharField(max_length=64)
执行manage.py命令创建表
菜单-tools-Run manager.py Task
$ makemigrations
$ migrate
booklist.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
<link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<table class="table table-hover table-bordered table-striped">
<thead>
<tr>
<th>id</th>
<th>name</th>
</tr>
</thead>
<tbody>
{% for book in book_list %}
<tr>
<td>{{ book.pk }}</td>
<td>{{ book.name }}</td>
</tr>
{% endfor %}
</tbody>
</table>
</div>
</div>
</div>
</body>
</html>
分页
导入模块 from django.core.paginator import Paginator,EmptyPage
Paginator 实现分页功能，跳转到那一页默认情况下需要通过浏览器手动输入
EmptyPage: 跳转到那一页默认情况下需要通过浏览器手动输入，如果输入的页数是负数或者超出范围就会有一场场EmptyPage，主要用作捕获异常
版本1
urls.py
from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^index/', views.index),
]
models.py
from django.db import models
# Create your models here.
class Book(models.Model):
title = models.CharField(max_length=32)
price = models.DecimalField(decimal_places=2, max_digits=8)
def __str__(self):
return '对象：%s'%self.title
views.py
from django.shortcuts import render, HttpResponse
# Create your views here.
from .models import Book
from django.core.paginator import Paginator,EmptyPage
def index(request):
# book_list = []
# for i in range(100):
# book = Book(title='book_%s' % i, price=i * i)
# book_list.append(book)
# Book.objects.bulk_create(book_list)
booklist=Book.objects.all()
# 分页器
paginator=Paginator(booklist,106)
print(paginator.count) # 数据总数
print(paginator.num_pages) # 总页数
print(paginator.page_range) #页码的列表
page_range=paginator.page_range
try:
current_pag=int(request.GET.get('page',1))
page1=paginator.page(current_pag) # 第一页数据的对象列表
# 显示某一页具体数据的两种方式:
print(page1.object_list)
# <QuerySet[ < Book: 对象：book_0 >, < Book: 对象：book_1 >, < Book: 对象：book_2 >, < Book: 对象：book_3 >, < Book: 对象：book_4 >] >
for i in page1:
print(i)
# 对象：book_0
# 对象：book_1
# 对象：book_2
# 对象：book_3
# 对象：book_4
except EmptyPage as e:
page1=paginator.page(1)
return render(request, 'index.html', {'page': page1,'page_range':page_range,'current_page':current_pag})
bootstrap中文网找到一个分页的样式 https://v3.bootcss.com/components/#pagination放入index.html，用户通过点击页码，就能跳转到页面
index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
<link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<table class="table table-hover table-bordered table-striped">
<thead>
<tr>
<th>id</th>
<th>title</th>
<th>price</th>
</tr>
</thead>
<tbody>
{% for book in page %}
<tr>
<td>{{ book.pk }}</td>
<td>{{ book.title }}</td>
<td>{{ book.price }}</td>
</tr>
{% endfor %}
</tbody>
</table>
</div>
</div>
</div>
<nav aria-label="Page navigation">
<ul class="pagination">
<li>
<a href="?page={{ current_page|add:-1 }}" aria-label="Previous">
<span aria-hidden="true">上一页</span>
</a>
</li>
{% for item in page_range %}
{% if current_page == item %}
<li class="active"><a href="?page={{ item }}">{{ item }}</a></li>
{% else %}
<li><a href="?page={{ item }}">{{ item }}</a></li>
{% endif %}
{% endfor %}
<li>
<a href="?page={{ current_page|add:1}}" aria-label="Next">
<span aria-hidden="true">下一页</span>
</a>
</li>
</ul>
</nav>
</body>
</html>
最终版本
urls.py
from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^index/', views.index),
]
views.py
from django.shortcuts import render, HttpResponse
# Create your views here.
from .models import Book
from django.core.paginator import Paginator, EmptyPage
def index(request):
# book_list = []
# for i in range(100):
# book = Book(title='book_%s' % i, price=i * i)
# book_list.append(book)
# Book.objects.bulk_create(book_list)
booklist = Book.objects.all()
# 分页器
paginator = Paginator(booklist, 60) # 分页，每一页106条数据对象
print(paginator.count) # 数据总数
print(paginator.num_pages) # 总页数
print(paginator.page_range) # 页码的列表
last_page=paginator.page_range[-1]
current_pag = int(request.GET.get('page', 1))
if paginator.num_pages > 11:
if current_pag - 5 < 1:
page_range = range(1, 12)
elif current_pag + 5 > paginator.num_pages:
page_range = range(paginator.num_pages - 11, paginator.num_pages + 1)
else:
page_range = range(current_pag - 5, current_pag + 6)
else:
page_range = paginator.page_range
try:
page1 = paginator.page(current_pag) # 某一页数据的对象列表
print(page1.has_next) # page1这一页是否有下一页
print(page1.next_page_number) # # page1这一页的下一页的页码
print(page1.has_previous) # page1这一页是否有上一页
print(page1.previous_page_number) #page1这一页的上一页的代码
# 显示某一页具体数据的两种方式:
print(page1.object_list)
# <QuerySet[ < Book: 对象：book_0 >, < Book: 对象：book_1 >, < Book: 对象：book_2 >, < Book: 对象：book_3 >, < Book: 对象：book_4 >] >
for i in page1:
print(i)
# 对象：book_0
# 对象：book_1
# 对象：book_2
# 对象：book_3
# 对象：book_4
except EmptyPage as e:
page1 = paginator.page(1)
return render(request, 'index.html', {'page': page1, 'page_range': page_range, 'current_page': current_pag,'last_page':last_page})
models.py
from django.db import models
class Book2(models.Model):
name=models.CharField(max_length=64)
执行manage.py命令创建表
菜单-tools-Run manager.py Task
$ makemigrations
$ migrate
index.html
bootstap不会提示的问题，解决方案是在本地导入bootstrap文件
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css"
integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap-theme.min.css"
integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">
<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<table class="table table-hover table-bordered table-striped">
<thead>
<tr>
<th>id</th>
<th>title</th>
<th>price</th>
</tr>
</thead>
<tbody>
{% for book in page %}
<tr>
<td>{{ book.pk }}</td>
<td>{{ book.title }}</td>
<td>{{ book.price }}</td>
</tr>
{% endfor %}
</tbody>
</table>
</div>
</div>
</div>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<nav aria-label="Page navigation">
<ul class="pagination center line-block">
<li>
<a href="?page=1" aria-label="Previous">
<span aria-hidden="true">第一页</span>
</a>
</li>
{% if page.has_previous %}
<li>
<a href="?page={{ page.previous_page_number }}" aria-label="Previous">
<span aria-hidden="true">上一页</span>
</a>
</li>
{% else %}
<li>
<span aria-hidden="true">上一页</span>
</li>
{% endif %}
{% for item in page_range %}
{% if current_page == item %}
<li class="active"><a href="?page={{ item }}">{{ item }}</a></li>
{% else %}
<li class="disabled"><a href="?page={{ item }}">{{ item }}</a></li>
{% endif %}
{% endfor %}
{% if page.has_next %}
<li>
<a href="?page={{ page.next_page_number }}" aria-label="Next">
<span aria-hidden="true">下一页</span>
</a>
</li>
{% else %}
<li class="disabled">
<span aria-hidden="true">下一页</span>
</li>
{% endif %}
<li>
<a href="?page={{ last_page }}" aria-label="Previous">
<span aria-hidden="true">最后一页</span>
</a>
</li>
</ul>
</nav>
</div>
</div>
</div>
</body>
</html>
