Django组件-分页器
1 Django的分页器（paginator）简介
在页面显示分页数据，需要用到Django分页器组件
from django.core.paginator import Paginator
Paginator对象： paginator = Paginator(user_list, 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 page对象：page=paginator.page(1) # 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
2 应用View层
from django.shortcuts import render,HttpResponse # Create your views here. from app01.models import * from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger def index(request): ''' 批量导入数据: Booklist=[] for i in range(100): Booklist.append(Book(title="book"+str(i),price=30+i*i)) Book.objects.bulk_create(Booklist) ''' ''' 分页器的使用: book_list=Book.objects.all() paginator = Paginator(book_list, 10) print("count:",paginator.count) #数据总数 print("num_pages",paginator.num_pages) #总页数 print("page_range",paginator.page_range) #页码的列表 page1=paginator.page(1) #第1页的page对象 for i in page1: #遍历第1页的所有数据对象 print(i) print(page1.object_list) #第1页的所有数据 page2=paginator.page(2) print(page2.has_next()) #是否有下一页 print(page2.next_page_number()) #下一页的页码 print(page2.has_previous()) #是否有上一页 print(page2.previous_page_number()) #上一页的页码 # 抛错 #page=paginator.page(12) # error:EmptyPage #page=paginator.page("z") # error:PageNotAnInteger ''' book_list=Book.objects.all() paginator = Paginator(book_list, 10) page = request.GET.get('page',1) currentPage=int(page) try: print(page) book_list = paginator.page(page) except PageNotAnInteger: book_list = paginator.page(1) except EmptyPage: book_list = paginator.page(paginator.num_pages) return render(request,"index.html",{"book_list":book_list,"paginator":paginator,"currentPage":currentPage})
3 模版层 index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"> </head> <body> <div class="container"> <h4>分页器</h4> <ul> {% for book in book_list %} <li>{{ book.title }} -----{{ book.price }}</li> {% endfor %} </ul> <ul class="pagination" id="pager"> {% if book_list.has_previous %} <li class="previous"><a href="/index/?page={{ book_list.previous_page_number }}">上一页</a></li> {% else %} <li class="previous disabled"><a href="#">上一页</a></li> {% endif %} {% for num in paginator.page_range %} {% if num == currentPage %} <li class="item active"><a href="/index/?page={{ num }}">{{ num }}</a></li> {% else %} <li class="item"><a href="/index/?page={{ num }}">{{ num }}</a></li> {% endif %} {% endfor %} {% if book_list.has_next %} <li class="next"><a href="/index/?page={{ book_list.next_page_number }}">下一页</a></li> {% else %} <li class="next disabled"><a href="#">下一页</a></li> {% endif %} </ul> </div> </body> </html>
4 扩展
''' 显示左5，右5，总共11个页， 1 如果总页码大于11 1.1 if 当前页码减5小于1，要生成1到12的列表（顾头不顾尾，共11个页码） page_range=range(1,12) 1.2 elif 当前页码+5大于总页码，生成当前页码减10，到当前页码加1的列表（顾头不顾尾，共11个页码） page_range=range(paginator.num_pages-10,paginator.num_pages+1) 1.3 else 生成当前页码-5，到当前页码+6的列表 page_range=range(current_page_num-5,current_page_num+6) 2 其它情况，生成的列表就是pageinator的page_range page_range=paginator.page_range '''
def index(request): book_list=Book.objects.all() paginator = Paginator(book_list, 15) page = request.GET.get('page',1) currentPage=int(page) # 如果页数十分多时，换另外一种显示方式
if paginator.num_pages>11: if currentPage-5<1: pageRange=range(1,11) elif currentPage+5>paginator.num_pages: pageRange=range(currentPage-5,paginator.num_pages+1) else: pageRange=range(currentPage-5,currentPage+5) else: pageRange=paginator.page_range try: print(page) book_list = paginator.page(page) except PageNotAnInteger: book_list = paginator.page(1) except EmptyPage: book_list = paginator.page(paginator.num_pages) return render(request,"index.html",locals())
def page_test(request): # book_list=[] # for i in range(100): # book=Book(name='book%s'%i,price=10+i,pub_date='2018-09-18',publish_id=1) # book_list.append(book) # Book.objects.bulk_create(book_list,10) book_list=Book.objects.all() # 生成paginator对象，传入书籍列表，每页10条数据 paginator=Paginator(book_list,3) # 总页码数 print(paginator.num_pages) # 页码列表 print(paginator.page_range) # 总数据 print(paginator.count) # 获取页面传来的页码 current_page=int(request.GET.get('page',1)) page_range=[] # 左5 右5 # 获取页面传来的页码的page对象 try: page=paginator.page(current_page) # print(page.has_next()) #是否有下一页 # print(page.next_page_number()) #下一页的页码 # print(page.has_previous()) #是否有上一页 # print(page.previous_page_number()) #上一页的页码 # 循环打印出当页对象 for i in page: print(i) except Exception as e: current_page=1 page = paginator.page(1) if paginator.num_pages>11: if current_page+5>paginator.num_pages: page_range=range(paginator.num_pages-10,paginator.num_pages+1) elif current_page-5<1: page_range=range(1,12) else: page_range=range(current_page-5,current_page+6) else: page_range=paginator.page_range return render(request,'page_test.html',locals())
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.min.css"> <title>Title</title> </head> <body> <ul> {% for foo in page %} <li>{{ foo.name }}</li> {% endfor %} </ul> <nav aria-label="Page navigation"> <ul class="pagination"> {% if page.has_previous %} <li> <a href="/page_test/?page={{ page.previous_page_number }}" aria-label="Previous"> <span aria-hidden="true">上一页</span> </a> </li> {% else %} <li class="disabled"> <a href="#" aria-label="Previous"> <span aria-hidden="true">上一页</span> </a> </li> {% endif %} {% for foo in page_range %} {% if current_page == foo %} <li class="active"><a href="/page_test/?page={{ foo }}">{{ foo }}</a></li> {% else %} <li><a href="/page_test/?page={{ foo }}">{{ foo }}</a></li> {% endif %} {% endfor %} {% if page.has_next %} <li> <a href="/page_test/?page={{ page.next_page_number }}" aria-label="Next"> <span aria-hidden="true">下一页</span> </a> </li> {% else %} <li class="disabled"> <a href="#" aria-label="Next"> <span aria-hidden="true">下一页</span> </a> </li> {% endif %} </ul> </nav> </body> </html>
使用：
#views.py from django.shortcuts import render, HttpResponse # Create your views here. from app01.models import * from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger def index(request): obj_list = Book.objects.all() paginator = Paginator(obj_list,9) # 每页显示行数 try: current_page = int(request.GET.get("page")) # 防止非数字 except: current_page = 1 ######################################################### show_page = 11 #默认显示页数 half = int((show_page - 1) / 2) all_pager = paginator.num_pages #总页数 # 如果数据总页数 < 11 if all_pager < show_page: begin = 1 stop = all_pager + 1 # 如果数据总页数 > 11 else: # 如果当前页 <=5,永远显示1,11 if current_page <= half: begin = 1 stop = show_page + 1 else: if current_page + half > all_pager: begin = all_pager - show_page + 1 stop = all_pager + 1 else: begin = current_page - half stop = current_page + half + 1 page_range = range(begin,stop) ######################################################### try: obj_list = paginator.page(current_page) except PageNotAnInteger: obj_list = paginator.page(1) except EmptyPage: obj_list = paginator.page(paginator.num_pages) # return render(request,"index.html",locals()) return render(request, "index.html", {"obj_list": obj_list, "current_page": current_page, "page_range": page_range}) ''' 批量导入数据: Booklist=[] for i in range(100): Booklist.append(Book(title="book"+str(i),price=30+i*i)) Book.objects.bulk_create(Booklist) 分页器的使用: obj_list=Book.objects.all() paginator = Paginator(obj_list, 10) #每页显示10条 print("count:",paginator.count) #数据总数 print("num_pages",paginator.num_pages) #总页数 print("page_range",paginator.page_range) #页码的列表 page1=paginator.page(1) #第1页的page对象 #显示某一页具体数据的两种方式： #方式1 for i in page1: #遍历第1页的所有数据对象 print(i) #方式2 print(page1.object_list) #第1页的所有数据 page2=paginator.page(2) print(page2.has_next()) #是否有下一页 print(page2.next_page_number()) #下一页的页码 print(page2.has_previous()) #是否有上一页 print(page2.previous_page_number()) #上一页的页码 #当前页 current_page=int(request.GET.get("page",1)) obj_list=paginator.page(current_page) for i in obj_list: #遍历当前页的所有数据对象 print(i) # 抛错 #page=paginator.page(12) # error:EmptyPage #page=paginator.page("z") # error:PageNotAnInteger '''
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"> </head> <body> <div class="container"> <h4>分页器</h4> <ul> {% for row in obj_list %} <li>{{ row.title }} -----{{ row.price }}</li> {% endfor %} </ul> <nav aria-label="Page navigation"> <ul class="pagination" id="pager"> {% if obj_list.has_previous %} <li class="previous"><a href="?page={{ obj_list.previous_page_number }}">上一页</a></li> {% else %} <li class="previous disabled"><a href="">上一页</a></li> {% endif %} {% for num in page_range %} {% if num == current_page %} <li class="item active"><a href="?page={{ num }}">{{ num }}</a></li> {% else %} <li class="item"><a href="?page={{ num }}">{{ num }}</a></li> {% endif %} {% endfor %} {% if obj_list.has_next %} <li class="next"><a href="?page={{ obj_list.next_page_number }}">下一页</a></li> {% else %} <li class="next disabled"><a href="">下一页</a></li> {% endif %} </ul> </nav> </div> </body> </html>
自定义分页
""" 分页组件 """ class Pagination(object): def __init__(self, current_page, all_count, base_url, query_params, per_page=20, pager_page_count=11): """ 分页初始化 :param current_page: 当前页码 :param per_page: 每页显示数据条数 :param all_count: 数据库中总条数 :param base_url: 基础URL :param query_params: QueryDict对象，内部含所有当前URL的原条件 :param pager_page_count: 页面上最多显示的页码数量 """ self.base_url = base_url try: self.current_page = int(current_page) if self.current_page <= 0: raise Exception() except Exception as e: self.current_page = 1 self.query_params = query_params self.per_page = per_page self.all_count = all_count self.pager_page_count = pager_page_count pager_count, b = divmod(all_count, per_page) if b != 0: pager_count += 1 self.pager_count = pager_count half_pager_page_count = int(pager_page_count / 2) self.half_pager_page_count = half_pager_page_count @property def start(self): """ 数据获取值起始索引 :return: """ return (self.current_page - 1) * self.per_page @property def end(self): """ 数据获取值结束索引 :return: """ return self.current_page * self.per_page def page_html(self): """ 生成HTML页码 :return: """ # 如果数据总页码pager_count<11 pager_page_count if self.pager_count < self.pager_page_count: pager_start = 1 pager_end = self.pager_count else: # 数据页码已经超过11 # 判断： 如果当前页 <= 5 half_pager_page_count if self.current_page <= self.half_pager_page_count: pager_start = 1 pager_end = self.pager_page_count else: # 如果： 当前页+5 > 总页码 if (self.current_page + self.half_pager_page_count) > self.pager_count: pager_end = self.pager_count pager_start = self.pager_count - self.pager_page_count + 1 else: pager_start = self.current_page - self.half_pager_page_count pager_end = self.current_page + self.half_pager_page_count page_list = [] if self.current_page <= 1: prev = '<li><a href="#">上一页</a></li>' else: self.query_params['page'] = self.current_page - 1 prev = '<li><a href="%s?%s">上一页</a></li>' % (self.base_url, self.query_params.urlencode()) page_list.append(prev) for i in range(pager_start, pager_end + 1): self.query_params['page'] = i if self.current_page == i: tpl = '<li class="active"><a href="%s?%s">%s</a></li>' % ( self.base_url, self.query_params.urlencode(), i,) else: tpl = '<li><a href="%s?%s">%s</a></li>' % (self.base_url, self.query_params.urlencode(), i,) page_list.append(tpl) if self.current_page >= self.pager_count: nex = '<li><a href="#">下一页</a></li>' else: self.query_params['page'] = self.current_page + 1 nex = '<li><a href="%s?%s">下一页</a></li>' % (self.base_url, self.query_params.urlencode(),) page_list.append(nex) page_str = "".join(page_list) return page_str
##使用 from django.shortcuts import render, HttpResponse from utils.pagination import Pagination def index(request): # ==========begin all_count = Book.objects.all().count() query_params = request.GET.copy() query_params._mutable = True pager = Pagination( current_page=request.GET.get('page'), all_count=all_count, base_url=request.path_info, query_params=query_params, per_page=20, ) data_list = Book.objects.all()[pager.start:pager.end] # ==========end return render(request, 'index.html', {'data_list': data_list, 'pager': pager}) #========模板 """ <nav> <ul class="pagination"> {{ pager.page_html|safe }} </ul> </nav> """
