【django学习-23】分页功能

• 前言：当列表界面数据量大的时候，我们一般就要用到分页功能。
• 下面是已经封装好的组件，使用方法
  • 1.分页组件

"""
自定义的分页组件，以后如果想要使用这个分页组件，你需要做如下几件事：在视图函数中：def pretty_list(request):# 1.根据自己的情况去筛选自己的数据queryset = models.PrettyNum.objects.all()# 2.实例化分页对象page_object = Pagination(request, queryset)context = {"queryset": page_object.page_queryset,  # 分完页的数据"page_string": page_object.html()       # 生成页码}return render(request, 'pretty_list.html', context)在HTML页面中{% for obj in queryset %}{{obj.xx}}{% endfor %}<ul class="pagination">{{ page_string }}</ul>"""from django.utils.safestring import mark_safeclass 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（根据这个数据给他进行分页处理）:param page_size: 每页显示多少条数据:param page_param: 在URL中传递的获取分页的参数，例如：/pretty/list/?page=12:param plus: 显示当前页的 前或后几页（页码）"""from django.http.request import QueryDictimport copyquery_dict = copy.deepcopy(request.GET)query_dict._mutable = Trueself.query_dict = query_dictself.page_param = page_parampage = request.GET.get(page_param, "1")if page.isdecimal():page = int(page)else:page = 1self.page = pageself.page_size = page_sizeself.start = (page - 1) * page_sizeself.end = page * page_sizeself.page_queryset = queryset[self.start:self.end]total_count = queryset.count()total_page_count, div = divmod(total_count, page_size)if div:total_page_count += 1self.total_page_count = total_page_countself.plus = plusdef 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 = 1end_page = self.total_page_countelse:# 数据库中的数据比较多 > 11页。# 当前页<5时（小极值）if self.page <= self.plus:start_page = 1end_page = 2 * self.plus + 1else:# 当前页 > 5# 当前页+5 > 总页面if (self.page + self.plus) > self.total_page_count:start_page = self.total_page_count - 2 * self.plusend_page = self.total_page_countelse:start_page = self.page - self.plusend_page = self.page + self.plus# 页码page_str_list = []self.query_dict.setlist(self.page_param, [1])page_str_list.append('<li><a href="?{}">首页</a></li>'.format(self.query_dict.urlencode()))# 上一页if self.page > 1:self.query_dict.setlist(self.page_param, [self.page - 1])prev = '<li><a href="?{}">上一页</a></li>'.format(self.query_dict.urlencode())else:self.query_dict.setlist(self.page_param, [1])prev = '<li><a href="?{}">上一页</a></li>'.format(self.query_dict.urlencode())page_str_list.append(prev)# 页面for i in range(start_page, end_page + 1):self.query_dict.setlist(self.page_param, [i])if i == self.page:ele = '<li class="active"><a href="?{}">{}</a></li>'.format(self.query_dict.urlencode(), i)else:ele = '<li><a href="?{}">{}</a></li>'.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 = '<li><a href="?{}">下一页</a></li>'.format(self.query_dict.urlencode())else:self.query_dict.setlist(self.page_param, [self.total_page_count])prev = '<li><a href="?{}">下一页</a></li>'.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('<li><a href="?{}">尾页</a></li>'.format(self.query_dict.urlencode()))search_string = """<li><form style="float: left;margin-left: -1px" method="get"><input name="page"style="position: relative;float:left;display: inline-block;width: 80px;border-radius: 0;"type="text" class="form-control" placeholder="页码"><button style="border-radius: 0" class="btn btn-default" type="submit">跳转</button></form></li>"""page_str_list.append(search_string)page_string = mark_safe("".join(page_str_list))return page_string

• 2.前端修改

<div class="clearfix"><ul class="pagination">{{ page_string }}</ul></div>

• 3.视图函数

def pretty_list(request):""" 靓号列表 """data_dict = {}search_data = request.GET.get('q', "")if search_data:data_dict["mobile__contains"] = search_dataqueryset = models.PrettyNum.objects.filter(**data_dict).order_by("-level")page_object = Pagination(request, queryset)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)

• 4.效果展示