Django（十四）分页器（paginator）及自定义分页D
http://www.mamicode.com/info-detail-1724597.html
http://www.cnblogs.com/wupeiqi/articles/5246483.html
分页组件
- Django内置分页
- Paginator、 Page
- 页面：include
- 扩展Django的内置分页
- CustomPaginator(Paginator)
传入：
- 所有数据
- 当前页
- 每页显示30条
- 最多页面7个
- 自定义分页
传入：
- 所有数据的个数
- 当前页
- 每页显示30条
- 最多页面7个
Django内置分页
from django.shortcuts import render from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger L = [] for i in range(999): L.append(i) def index(request): current_page = request.GET.get('p') paginator = Paginator(L, 10) # per_page: 每页显示条目数量 # count: 数据总个数 # num_pages:总页数 # page_range:总页数的索引范围，如: (1,10),(1,200) # page: page对象 try: posts = paginator.page(current_page) # has_next 是否有下一页 # next_page_number 下一页页码 # has_previous 是否有上一页 # previous_page_number 上一页页码 # object_list 分页之后的数据列表 # number 当前页 # paginator paginator对象 except PageNotAnInteger: posts = paginator.page(1) except EmptyPage: posts = paginator.page(paginator.num_pages) return render(request, 'index.html', {'posts': posts}) views.py
<!DOCTYPE html> <html> <head lang="en"> <meta charset="UTF-8"> <title></title> </head> <body> <ul> {% for item in posts %} <li>{{ item }}</li> {% endfor %} </ul> <div class="pagination"> <span class="step-links"> {% if posts.has_previous %} <a href="?p={{ posts.previous_page_number }}">Previous</a> {% endif %} <span class="current"> Page {{ posts.number }} of {{ posts.paginator.num_pages }}. </span> {% if posts.has_next %} <a href="?p={{ posts.next_page_number }}">Next</a> {% endif %} </span> </div> </body> </html> Html
扩展内置分页
from django.shortcuts import render from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger class CustomPaginator(Paginator): def __init__(self, current_page, max_pager_num, *args, **kwargs): """ :param current_page: 当前页 :param max_pager_num:最多显示的页码个数 :param args: :param kwargs: :return: """ self.current_page = int(current_page) self.max_pager_num = max_pager_num super(CustomPaginator, self).__init__(*args, **kwargs) def page_num_range(self): # 当前页面 # self.current_page # 总页数 # self.num_pages # 最多显示的页码个数 # self.max_pager_num print(1) if self.num_pages < self.max_pager_num: return range(1, self.num_pages + 1) print(2) part = int(self.max_pager_num / 2) if self.current_page - part < 1: return range(1, self.max_pager_num + 1) print(3) if self.current_page + part > self.num_pages: return range(self.num_pages + 1 - self.max_pager_num, self.num_pages + 1) print(4) return range(self.current_page - part, self.current_page + part + 1) L = [] for i in range(999): L.append(i) def index(request): current_page = request.GET.get('p') paginator = CustomPaginator(current_page, 11, L, 10) # per_page: 每页显示条目数量 # count: 数据总个数 # num_pages:总页数 # page_range:总页数的索引范围，如: (1,10),(1,200) # page: page对象 try: posts = paginator.page(current_page) # has_next 是否有下一页 # next_page_number 下一页页码 # has_previous 是否有上一页 # previous_page_number 上一页页码 # object_list 分页之后的数据列表 # number 当前页 # paginator paginator对象 except PageNotAnInteger: posts = paginator.page(1) except EmptyPage: posts = paginator.page(paginator.num_pages) return render(request, 'index.html', {'posts': posts})
<!DOCTYPE html> <html> <head lang="en"> <meta charset="UTF-8"> <title></title> </head> <body> <ul> {% for item in posts %} <li>{{ item }}</li> {% endfor %} </ul> <div class="pagination"> <span class="step-links"> {% if posts.has_previous %} <a href="?p={{ posts.previous_page_number }}">Previous</a> {% endif %} {% for i in posts.paginator.page_num_range %} <a href="?p={{ i }}">{{ i }}</a> {% endfor %} {% if posts.has_next %} <a href="?p={{ posts.next_page_number }}">Next</a> {% endif %} </span> <span class="current"> Page {{ posts.number }} of {{ posts.paginator.num_pages }}. </span> </div> </body> </html>
使用模板include
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <ul> {% for row in posts.object_list %} <li>{{ row.name }}-{{ row.age }}</li> {% endfor %} </ul> {% include 'include/pager.html' %} </body> </html>
{% if posts.has_previous %} <a href="/index?p={{ posts.previous_page_number }}">up</a> {% else %} <a href="#">up</a> {% endif %} {% for i in posts.paginator.pager_num_range %} {% if i == posts.number %} <a style="font-size: 30px;" href="/index?p={{ i }}">{{ i }}</a> {% else %} <a href="/index?p={{ i }}">{{ i }}</a> {% endif %} {% endfor %} {% if posts.has_next %} <a href="/index?p={{ posts.next_page_number }}">down</a> {% else %} <a href="#">down</a> {% endif %} <span> {{ posts.number }}/{{ posts.paginator.num_pages }} </span>
自定义分页
分页功能在每个网站都是必要的，对于分页来说，其实就是根据用户的输入计算出应该在数据库表中的起始位置。
1、设定每页显示数据条数
2、用户输入页码（第一页、第二页...）
3、根据设定的每页显示条数和当前页码，计算出需要取数据表的起始位置
4、在数据表中根据起始位置取值，页面上输出数据
需求又来了，需要在页面上显示分页的页面。如：［上一页］［1］［2］［3］［4］［5］［下一页］
1、设定每页显示数据条数
2、用户输入页码（第一页、第二页...）
3、设定显示多少页号
4、获取当前数据总条数
5、根据设定显示多少页号和数据总条数计算出，总页数
6、根据设定的每页显示条数和当前页码，计算出需要取数据表的起始位置
7、在数据表中根据起始位置取值，页面上输出数据
8、输出分页html，如：［上一页］［1］［2］［3］［4］［5］［下一页］
from django.shortcuts import render from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger USER_LIST = [] for i in range(1,666): temp = {'name':'root'+str(i), 'age':i} USER_LIST.append(temp) def index2(request): from app01.pager import Pagination current_page = request.GET.get('p') page_obj = Pagination(666,current_page) data_list = USER_LIST[page_obj.start():page_obj.end()] return render(request,'index2.html',{'data':data_list,'page_obj':page_obj})
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css" /> </head> <body> <ul> {% for row in data %} <li>{{ row.name }}-{{ row.age }}</li> {% endfor %} </ul> {% for i in page_obj.pager_num_range %} <a href="/index2.html?p={{ i }}">{{ i }}</a> {% endfor %} <hr/> <ul class="pagination pagination-sm"> {{ page_obj.page_str|safe }} </ul> <div style="height: 300px;"></div> </body> </html>
class Pagination(object): def __init__(self,totalCount,currentPage,perPageItemNum=10,maxPageNum=7): # 数据总个数 self.total_count = totalCount # 当前页 try: v = int(currentPage) if v <= 0: v = 1 self.current_page = v except Exception as e: self.current_page = 1 # 每页显示的行数 self.per_page_item_num = perPageItemNum # 最多显示页面 self.max_page_num = maxPageNum def start(self): return (self.current_page-1) * self.per_page_item_num def end(self): return self.current_page * self.per_page_item_num @property def num_pages(self): """ 总页数 :return: """ # 666 # 10 a,b = divmod(self.total_count,self.per_page_item_num) if b == 0: return a return a+1 def pager_num_range(self): # self.num_pages() # self.num_pages # 当前页 #self.current_page # 最多显示的页码数量 11 #self.per_pager_num # 总页数 # self.num_pages if self.num_pages < self.max_page_num: return range(1,self.num_pages+1) # 总页数特别多 5 part = int(self.max_page_num/2) if self.current_page <= part: return range(1,self.max_page_num+1) if (self.current_page + part) > self.num_pages: return range(self.num_pages-self.max_page_num+1,self.num_pages+1) return range(self.current_page-part,self.current_page+part+1) def page_str(self): page_list = [] first = "<li><a href='/index2.html?p=1'>首页</a></li>" page_list.append(first) if self.current_page == 1: prev = "<li><a href='#'>上一页</a></li>" else: prev = "<li><a href='/index2.html?p=%s'>上一页</a></li>" %(self.current_page-1,) page_list.append(prev) for i in self.pager_num_range(): if i == self.current_page: temp = "<li class='active'><a href='/index2.html?p=%s'>%s</a></li>" %(i,i) else: temp = "<li><a href='/index2.html?p=%s'>%s</a></li>" % (i, i) page_list.append(temp) if self.current_page == self.num_pages: nex = "<li><a href='#'>下一页</a></li>" else: nex = "<li><a href='/index2.html?p=%s'>下一页</a></li>" % (self.current_page + 1,) page_list.append(nex) last = "<li><a href='/index2.html?p=%s'>尾页</a></li>" %(self.num_pages,) page_list.append(last) return ''.join(page_list)
总结，分页时需要做三件事：
- 创建处理分页数据的类
- 根据分页数据获取数据
- 输出分页HTML，即：［上一页］［1］［2］［3］［4］［5］［下一页］
