分页
自定义分页
def book_list(request): # 1. 查询所有的书籍数 data = models.Book.objects.all() # 统计下总数据条数 total_num = data.count() # 从URL中提取出来当前访问的具体页码数 try: current_page = int(request.GET.get("page")) except Exception as e: current_page = 1 print(current_page) # 定义每一页显示10条 per_page = 10 # 定义页面上最多显示多少个页码 show_page_num = 7 half_show_page_num = show_page_num // 2 # 当前数据总共需要多少页码 total_page, more = divmod(total_num, per_page) # 如果有余数，就把页码数+1 if more: total_page += 1 # 如果当前页码数大于总页码数，默认展示最后一页的数据 # current_page = total_page if current_page > total_page else current_page if current_page > total_page: current_page = total_page # 如果当前页码数小于1，默认展示第一页的数据 if current_page < 1: current_page = 1 # 求 页面上 需要展示的页码范围 if current_page - half_show_page_num <= 1: page_start = 1 page_end = show_page_num elif current_page + half_show_page_num >= total_page: page_end = total_page page_start = total_page - show_page_num + 1 else: page_start = current_page - half_show_page_num page_end = current_page + half_show_page_num print("{} -{}- {}".format(page_start, current_page, page_end)) print("=" * 120) # 当前页码应该展示的书籍数据 book_list = data[(current_page-1)*per_page:current_page*per_page] # 生成分页的页码 """ <li><a href="#">1</a></li> <li><a href="#">2</a></li> <li><a href="#">3</a></li> <li><a href="#">4</a></li> <li><a href="#">5</a></li> """ li_list = [] # 添加首页 li_list.append('<li><a href="/book_list/?page=1">首页</a></li>') # 添加上一页 if current_page <= 1: # 没有上一页 prev_html = '<li class="disabled"><a aria-label="Previous"><span aria-hidden="true">«</span></a></li>' else: prev_html = '<li><a href="/book_list/?page={}" aria-label="Previous"><span aria-hidden="true">«</span></a></li>'.format(current_page-1) li_list.append(prev_html) for i in range(page_start, page_end+1): if i == current_page: tmp = '<li class="active"><a href="/book_list/?page={0}">{0}</a></li>'.format(i) else: tmp = '<li><a href="/book_list/?page={0}">{0}</a></li>'.format(i) li_list.append(tmp) # 添加下一页 if current_page >= total_page: # 表示没有下一页 next_html = '<li class="disabled"><a aria-label="Previous"><span aria-hidden="true">»</span></a></li>' else: next_html = '<li><a href="/book_list/?page={}" aria-label="Previous"><span aria-hidden="true">»</span></a></li>'.format(current_page+1) li_list.append(next_html) # 添加尾页 li_list.append('<li><a href="/book_list/?page={}">尾页</a></li>'.format(total_page)) # 将生成的li标签 拼接成一个大的字符串 page_html = "".join(li_list) # print(page_html) # 2. 在页面上展示出来 return render(request, "book_list.html", {"book_list": book_list, "page_html": page_html})
class Page(object): """ 实现Django ORM数据的分页展示 使用说明： from utils import mypage page_obj = mypage.Page(total_num, current_page, 'publisher_list') publisher_list = data[page_obj.data_start:page_obj.data_end] page_html = page_obj.page_html() 为了显示效果，show_page_num最好使用奇数 """ def __init__(self, total_num, current_page, url_prefix, per_page=10, show_page_num=11): """ :param total_num: 数据的总条数 :param current_page: 当前访问的页码 :param url_prefix: 分页代码里a标签的前缀 :param per_page: 每一页显示多少条数据 :param show_page_num: 页面上最多显示多少个页码 """ self.total_num = total_num self.url_prefix = url_prefix self.per_page = per_page self.show_page_num = show_page_num # 通过初始化传入的值计算得到的值 self.half_show_page_num = self.show_page_num // 2 # 当前数据总共需要多少页码 total_page, more = divmod(self.total_num, self.per_page) # 如果有余数，就把页码数+1 if more: total_page += 1 self.total_page = total_page # 对传进来的当前页码数做有效性校验 try: current_page = int(current_page) except Exception as e: current_page = 1 # 如果当前页码数大于总页码数，默认展示最后一页的数据 # current_page = total_page if current_page > total_page else current_page if current_page > self.total_page: current_page = self.total_page # 如果当前页码数小于1，默认展示第一页的数据 if current_page < 1: current_page = 1 self.current_page = current_page # 求 页面上 需要展示的页码范围 if self.current_page - self.half_show_page_num <= 1: page_start = 1 page_end = show_page_num elif self.current_page + self.half_show_page_num >= self.total_page: page_end = self.total_page page_start = self.total_page - self.show_page_num + 1 else: page_start = self.current_page - self.half_show_page_num page_end = self.current_page + self.half_show_page_num self.page_start = page_start self.page_end = page_end @property def data_start(self): # 返回当前页应该从哪儿开始切数据 return (self.current_page-1)*self.per_page @property def data_end(self): # 返回当前页应该切到哪里为止 return self.current_page*self.per_page def page_html(self): li_list = [] # 添加首页 li_list.append('<li><a href="/{}/?page=1">首页</a></li>'.format(self.url_prefix)) # 添加上一页 if self.current_page <= 1: # 没有上一页 prev_html = '<li class="disabled"><a aria-label="Previous"><span aria-hidden="true">«</span></a></li>' else: prev_html = '<li><a href="/{}/?page={}" aria-label="Previous"><span aria-hidden="true">«</span></a></li>'.format(self.url_prefix, self.current_page - 1) li_list.append(prev_html) for i in range(self.page_start, self.page_end + 1): if i == self.current_page: tmp = '<li class="active"><a href="/{0}/?page={1}">{1}</a></li>'.format(self.url_prefix, i) else: tmp = '<li><a href="/{0}/?page={1}">{1}</a></li>'.format(self.url_prefix, i) li_list.append(tmp) # 添加下一页 if self.current_page >= self.total_page: # 表示没有下一页 next_html = '<li class="disabled"><a aria-label="Previous"><span aria-hidden="true">»</span></a></li>' else: next_html = '<li><a href="/{}/?page={}" aria-label="Previous"><span aria-hidden="true">»</span></a></li>'.format( self.url_prefix, self.current_page + 1) li_list.append(next_html) # 添加尾页 li_list.append('<li><a href="/{}/?page={}">尾页</a></li>'.format(self.url_prefix, self.total_page)) # 将生成的li标签 拼接成一个大的字符串 page_html = "".join(li_list) return page_html
page_obj = mypage.Page(total_num, current_page, 'publisher_list', per_page=20) publisher_list = data[page_obj.data_start:page_obj.data_end] page_html = page_obj.page_html() return render(request, "publisher_list.html", {"publisher_list": publisher_list, "page_html": page_html})