分页：pagination.py

'''
一、在视图函数中：
def pretty_list(request):
# 0.搜索数据
data_dict = {}
search_data = request.GET.get('q', '')
if search_data:
data_dict['mobile__contains'] = search_data
# 1.根据情况筛选数据
queryset = models.PrettyNum.objects.filter(**data_dict).order_by('-id')
# 2.实例化分页对象
page_object = Pagination(request, queryset,page_size=20)
context = {
'search_data': search_data,
'queryset': page_object.page_queryset, # 分完页的数据
'page_string': page_object.html() # 页码
}
return render(request, 'pretty_list.html', context)
二、在HTML中：

{{ page_string }}

'''
from django.utils.safestring import mark_safe

class Pagination(object):
def init(self, request, queryset, page_size=10, page_param='page', plus=5):
'''
:param request: 请求的对象
:param queryset: 符合条件的数据，根据他进行分页
:param page_size:每页显示多少条数据
:param page_param:在URL中传递的分页的参数：/pretty/list/?page=page_param
:param plus:显示当前面的前后几页。
'''
# 保存搜索条件
import copy
query_dict = copy.deepcopy(request.GET)
query_dict._mutable = True
self.query_dict = query_dict
self.page_param = page_param

page = request.GET.get(page_param, '1')
if page.isdecimal():
page = int(page)
else:
page = 1
self.page = page
self.page_size = page_size
self.start = (page - 1) * page_size
self.end = page * page_size

self.page_queryset = queryset[self.start:self.end]

数据库的总条数

total_count = queryset.count()

总页码

total_page_count, div = divmod(total_count, page_size)
if div:
total_page_count += 1
self.total_page_count = total_page_count
self.plus = plus

def html(self):
# 计算出，显示当前页的前5页、后5页
if self.total_page_count <= 2 * self.plus + 1:
# 数据库中的数据比较少，都没有达到11页，
start_page = 1
end_page = self.total_page_count
else:
# 数据库中的数据比较多，大于11页

当前页<5时

if self.page <= self.plus:
start_page = 1
end_page = 2 * self.plus + 1
else:
# 当前>5时：当前页+5>总页面
if (self.page + self.plus) > self.total_page_count:
start_page = self.total_page_count - 2 * self.plus
end_page = self.total_page_count
else:
start_page = self.page - self.plus
end_page = self.page + self.plus

页码

page_str_list = []

self.query_dict.setlist(self.page_param, [1])
page_str_list.append('

首页

'.format(self.query_dict.urlencode()))

上一页

if self.page > 1:
self.query_dict.setlist(self.page_param, [self.page - 1])
prev = '

上一页

'.format(self.query_dict.urlencode())
else:
self.query_dict.setlist(self.page_param, [1])
prev = '

上一页

'.format(self.query_dict.urlencode())
page_str_list.append(prev)

for i in range(start_page, end_page + 1):
self.query_dict.setlist(self.page_param, [i])
if i == self.page:
ele = '

{}

'.format(self.query_dict.urlencode(), i)
else:
ele = '

{}

'.format(self.query_dict.urlencode(), i)

page_str_list.append(ele)

下一页

if self.page < self.total_page_count:
self.query_dict.setlist(self.page_param, [self.page + 1])
prev = '

下一页

'.format(self.query_dict.urlencode())
else:
self.query_dict.setlist(self.page_param, [self.total_page_count])
prev = '

下一页

'.format(self.query_dict.urlencode())
page_str_list.append(prev)

尾页

self.query_dict.setlist(self.page_param, [self.total_page_count])
page_str_list.append('

尾页

'.format(self.query_dict.urlencode()))

search_string = '''

跳转

'''
page_str_list.append(search_string)

page_string = mark_safe(''.join(page_str_list))
return page_string