序列化组件
#
# from django.core import serializers # django自带的一个小型的序列化工具
# def reg(request):
# user_list = models.User.objects.all()
# res = serializers.serialize('json',user_list)
# return render(request,'index.html',locals())
sweetalert搭建页面
#
# 自定义分页器
# 1 bulk_create() 批量插入数据
# # for i in range(1000):
# # models.Book.objects.create(title='第%s本书'%i)
# # 上面这种方式 效率极低
#
# l = []
# for i in range(10000):
# l.append(models.Book(title='第%s本书'%i))
# models.Book.objects.bulk_create(l) # 批量插入数据
#
#
# 自定义分页器的使用
# 后端代码
# book_list = models.Book.objects.all()
# current_page = request.GET.get("page",1)
# all_count = book_list.count()
# page_obj = Pagination(current_page=current_page,all_count=all_count,per_page_num=10,pager_count=5)
# page_queryset = book_list[page_obj.start:page_obj.end]
# 前端代码
# {% for book in page_queryset %}
# <p>{{ book.title }}</p>
# {% endfor %}
# {{ page_obj.page_html|safe }}
#
# MTV与MVC模型
# django框架 自称为是MTV框架
# M:models
# T:templates
# V:views
#
# MVC
# M:models
# V:views
# C:controller 控制器(urls)
# 本质:MTV其实也是MVC
from django.db import models
# Create your models here.
class User(models.Model):
username = models.CharField(max_length=32)
age = models.IntegerField()
choices = (
(1,'男'),(2,'女'),(3,'其他')
)
gender = models.IntegerField(choices=choices)
"""
1 存choice里面罗列的数字与中文对应关系
print(user_obj.get_gender_display())
只要是choices字段 在获取数字对应的注释 固定语法
get_choices字段名_display()
2 存没有罗列迟来的数字
不会报错 还是展示数字
"""
class Book(models.Model):
title = models.CharField(max_length=32)
class Pagination(object):
def __init__(self, current_page, all_count, per_page_num=2, pager_count=11):
"""
封装分页相关数据
:param current_page: 当前页
:param all_count: 数据库中的数据总条数
:param per_page_num: 每页显示的数据条数
:param pager_count: 最多显示的页码个数
用法:
queryset = model.objects.all()
page_obj = Pagination(current_page,all_count)
page_data = queryset[page_obj.start:page_obj.end]
获取数据用page_data而不再使用原始的queryset
获取前端分页样式用page_obj.page_html
"""
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page < 1:
current_page = 1
self.current_page = current_page
self.all_count = all_count
self.per_page_num = per_page_num
# 总页码
all_pager, tmp = divmod(all_count, per_page_num)
if tmp:
all_pager += 1
self.all_pager = all_pager
self.pager_count = pager_count
self.pager_count_half = int((pager_count - 1) / 2)
@property
def start(self):
return (self.current_page - 1) * self.per_page_num
@property
def end(self):
return self.current_page * self.per_page_num
def page_html(self):
# 如果总页码 < 11个：
if self.all_pager <= self.pager_count:
pager_start = 1
pager_end = self.all_pager + 1
# 总页码 > 11
else:
# 当前页如果<=页面上最多显示11/2个页码
if self.current_page <= self.pager_count_half:
pager_start = 1
pager_end = self.pager_count + 1
# 当前页大于5
else:
# 页码翻到最后
if (self.current_page + self.pager_count_half) > self.all_pager:
pager_end = self.all_pager + 1
pager_start = self.all_pager - self.pager_count + 1
else:
pager_start = self.current_page - self.pager_count_half
pager_end = self.current_page + self.pager_count_half + 1
page_html_list = []
# 添加前面的nav和ul标签
page_html_list.append('''
<nav aria-label='Page navigation>'
<ul class='pagination'>
''')
first_page = '<li><a href="?page=%s">首页</a></li>' % (1)
page_html_list.append(first_page)
if self.current_page <= 1:
prev_page = '<li class="disabled"><a href="#">上一页</a></li>'
else:
prev_page = '<li><a href="?page=%s">上一页</a></li>' % (self.current_page - 1,)
page_html_list.append(prev_page)
for i in range(pager_start, pager_end):
if i == self.current_page:
temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i,)
else:
temp = '<li><a href="?page=%s">%s</a></li>' % (i, i,)
page_html_list.append(temp)
if self.current_page >= self.all_pager:
next_page = '<li class="disabled"><a href="#">下一页</a></li>'
else:
next_page = '<li><a href="?page=%s">下一页</a></li>' % (self.current_page + 1,)
page_html_list.append(next_page)
last_page = '<li><a href="?page=%s">尾页</a></li>' % (self.all_pager,)
page_html_list.append(last_page)
# 尾部添加标签
page_html_list.append('''
</nav>
</ul>
''')
return ''.join(page_html_list)
from __future__ import unicode_literals
from django.db import migrations, models
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='User',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('username', models.CharField(max_length=32)),
('age', models.IntegerField()),
('gender', models.IntegerField(choices=[(1, '男'), (2, '女'), (3, '其他')])),
],
),
]
from __future__ import unicode_literals
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('app01', '0001_initial'),
]
operations = [
migrations.CreateModel(
name='Book',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('title', models.CharField(max_length=32)),
],
),
]