django_分页

一、基础篇

django_分页_第1张图片
image.png

=
view模块处理

li = []
for i in range(101):
    li.append(i)
def user_list(request):
    #当page 关键字不存在时 默认1
    current_page = request.GET.get('page',1)
    current_page = int(current_page)
    #页数减-1*10,切片的起始位置
    start = (current_page-1)*10
    # 页数减*10,切片的结束位置
    end = (current_page)*10
    data = li[start:end]
    #显示页数,因为页面没有循环数字的方法,所以后台处理
    page_num,mod_num = divmod(len(li),10)
    #余数不为0页数加一
    if mod_num:
        page_num += 1
    temp_list = []
    for i in range(1,page_num+1):
        if i==current_page:
            temp = '%s'%(i,i)
        else:
            temp = '%s'%(i,i)
        temp_list.append(temp)
    temp_num = ''.join(temp_list)
    return render(request,'user_list.html',{'num':temp_num,'data':data})

html 页面




    
    Title
    


    {% for i in data %}
  • {{ i }}
  • {% endfor %}

{{ num|safe }}

二、讲解

对页数限制的讲解

page_count   显示条数
current_page 当前页数
page_num     总页数
11           页码

总页数小于实际展示页数
总页数大于实际展示页数

前提条件总页数11时 

    当前页<=6
        开始页1
        结束页11
    当前页>6
        开始页=当前页-5
        结束页=当前页+6
        当前页+5>总页数
            结束页=总页数+1
            开始页=总页数-10

转换成代码

if page_num<11:
    start_index = 1
    end_index = page_num
else:
    if current_page<=6:  
        start_index = 1
        end_index = 11
    else:
        start_index = current_page -5
        end_index = current_page +6
        if current_page+5>page_num:
            end_index = page_num+1
            start_index = page_num-10

上一页/下一页操作

上一页
当前页等于1时
    上一页功能失效
当前页大于1时
    当前页-1

下一页
当前页等于总页数时
    下一页功能失效
当前页小于总页数时
    当前页+1

代码如下

if current_page ==1:
    prev = '上一页'
else:
    prev = '上一页'%(current_page-1)


if current_page ==page_num:
    prev = '下一页'
else:
    prev = '下一页'%(current_page+1)

跳转代码如下:

 jump ='''
    GO
    
    '''

分页整体代码如下:

def user_list(request):
    page_count = 10
    #当page 关键字不存在时 默认1
    current_page = request.GET.get('page',1)
    current_page = int(current_page)
    #页数减-1*10,切片的起始位置
    start = (current_page-1)*page_count
    # 页数减*10,切片的结束位置
    end = (current_page)*page_count
    data = li[start:end]
    #显示页数,因为页面没有循环数字的方法,所以后台处理
    page_num,mod_num = divmod(len(li),page_count)
    #余数不为0页数加一
    if mod_num:
        page_num += 1
    temp_list = []

    #显示最大页数
    max_page = 11
    if page_numpage_num:
                start_index = page_num-max_page+1
                end_indx = page_num+1

    if current_page == 1:
        prev = '上一页'
    else:
        prev = '上一页' % (current_page - 1)
    temp_list.append(prev)
    # 起始页
    for i in range(int(start_index),int(end_indx)):
        if i==current_page:
            temp = '%s'%(i,i)
        else:
            temp = '%s'%(i,i)
        temp_list.append(temp)
    if current_page == page_num:
        prev = '上一页'
    else:
        prev = '上一页' % (current_page + 1)
    temp_list.append(prev)
    jump ='''
    GO
    
    '''
    temp_list.append(jump)
    temp_num = ''.join(temp_list)
    return render(request,'user_list.html',{'num':temp_num,'data':data})

三、打包成类

class page():
    '''
    start:获取每页的第一条数据
    end:获取每页的最后一条数据
    all_count: 获取总页数
    page_str: 分页展示,上一页,下一页,跳转
    '''
    def __init__(self,current_page,date_count,page_count=10,max_page = 11):
        '''
        :param current_page: 当前页数,通过request.GET获取
        :param date_count:   数据总个数,用divmod进行取余判断总页数
        :param page_count:   每页显示数据的个数
        :param max_page:     网页可显示的最大总页数
        '''
        self.current_page = current_page
        self.data_count = date_count
        self.page_count = page_count
        self.max_page = max_page

    @property
    def start(self):
        '''
        :return: (当前页-1)*每页展示条数==每页展示数据的第一条
        '''
        return (self.current_page-1)*self.page_count
    @property
    def end(self):
        '''
        :return:  当前页*每页展示条数==每页展示数据的最后一条
        '''
        return self.current_page*self.page_count

    @property
    def all_count(self):
        '''
        :param page_all:   取余的方法,得到商
        :param mod_num:    取余的方法,得到余
        :return:           返回实际总页数
        '''
        v =self.data_count
        page_all, mod_num = divmod(v, self.page_count)
        if mod_num:
            page_all += 1
        return page_all

    def page_str(self):
        temp_list = []
        if self.all_count < self.max_page:
            start_index = 1
            end_indx = self.max_page
        else:
            if self.current_page <= (self.max_page + 1) / 2:
                start_index = 1
                end_indx =self.max_page
            else:
                start_index = self.current_page - (self.max_page - 1) / 2
                end_indx = self.current_page + (self.max_page + 1) / 2
                if self.current_page + (self.max_page - 1) / 2 > self.all_count:
                    start_index = self.all_count - self.max_page + 1
                    end_indx = self.all_count + 1

        if self.current_page == 1:
            prev = '上一页'
        else:
            prev = '上一页' % (self.current_page - 1)
        temp_list.append(prev)
        # 起始页
        for i in range(int(start_index), int(end_indx)):
            if i == self.current_page:
                temp = '%s' % (i, i)
            else:
                temp = '%s' % (i, i)
            temp_list.append(temp)
        if self.current_page ==self.all_count:
            prev = '上一页'
        else:
            prev = '上一页' % (self.current_page + 1)
        temp_list.append(prev)
        jump = '''
           GO
           
           '''
        temp_list.append(jump)
        temp_num = ''.join(temp_list)
        return temp_num

使用类

def user_list(request):
    page_count = 10
    #当page 关键字不存在时 默认1
    current_page = request.GET.get('page',1)
    current_page = int(current_page)
    #创建分页对象
    page_obj = page(current_page,len(li))
    #每页数据的起始数据,结束数据
    data = li[page_obj.start:page_obj.end]
    temp_num=page_obj.page_str()
    return render(request,'user_list.html',{'num':temp_num,'data':data})

  • 直接使用版本

__author__ = 'Administrator'
from django.utils.safestring import mark_safe


class Pagination(object):
    def __init__(self, current_page, data_count, per_page_count=1, pager_num=7):
        try:
            self.current_page = int(current_page)
        except Exception as e:
            self.current_page = 1
        self.data_count = data_count
        self.per_page_count = per_page_count
        self.pager_num = pager_num

    @property
    def start(self):
        return (self.current_page - 1) * self.per_page_count

    @property
    def end(self):
        return self.current_page * self.per_page_count

    @property
    def total_count(self):
        v, y = divmod(self.data_count, self.per_page_count)
        if y:
            v += 1
        return v

    def page_str(self, base_url):
        page_list = []

        if self.total_count < self.pager_num:
            start_index = 1
            end_index = self.total_count + 1
        else:
            if self.current_page <= (self.pager_num + 1) / 2:
                start_index = 1
                end_index = self.pager_num + 1
            else:
                start_index = self.current_page - (self.pager_num - 1) / 2
                end_index = self.current_page + (self.pager_num + 1) / 2
                if (self.current_page + (self.pager_num - 1) / 2) > self.total_count:
                    end_index = self.total_count + 1
                    start_index = self.total_count - self.pager_num + 1

        if self.current_page == 1:
            prev = '
  • 上一页
  • ' else: prev = '
  • 上一页
  • ' % (base_url, self.current_page - 1,) page_list.append(prev) for i in range(int(start_index), int(end_index)): if i == self.current_page: temp = '
  • %s
  • ' % (base_url, i, i) else: temp = '
  • %s
  • ' % (base_url, i, i) page_list.append(temp) if self.current_page == self.total_count: nex = '
  • 下一页
  • ' else: nex = '
  • 下一页
  • ' % (base_url, self.current_page + 1,) page_list.append(nex) # jump = """ # GO # # """ % (base_url,) # # page_list.append(jump) page_str = mark_safe("".join(page_list)) return page_str

    你可能感兴趣的:(django_分页)