python_fullstack—Django框架(八)-Pagination分页实现

Django Pagination

一、自定义分页

1、基础版自定义分页

data = []

for i in range(1, 302):
    tmp = {"id": i, "name": "yang-{}".format(i)}
    data.append(tmp)

print(data)


def user_list(request):

    # user_list = data[0:10]
    # user_list = data[10:20]
    try:
        current_page = int(request.GET.get("page"))
    except Exception as e:
        current_page = 1

    per_page = 10

    # 数据总条数
    total_count = len(data)
    # 总页码
    total_page, more = divmod(total_count, per_page)
    if more:
        total_page += 1

    # 页面最多显示多少个页码
    max_show = 11
    half_show = int((max_show-1)/2)

    if current_page <= half_show:
        show_start = 1
        show_end = max_show
    else:
        if current_page + half_show >= total_page:
            show_start = total_page - max_show
            show_end = total_page
        else:
            show_start = current_page - half_show
            show_end = current_page + half_show

    # 数据库中获取数据
    data_start = (current_page - 1) * per_page
    data_end = current_page * per_page

    user_list = data[data_start:data_end]

    # 生成页面上显示的页码
    page_html_list = []
    # 加首页
    first_li = '
首页
'
    page_html_list.append(first_li)
    # 加上一页
    if current_page == 1:
        prev_li = '
上一页
'
    else:
        prev_li = '
上一页
'.format(current_page - 1)
    page_html_list.append(prev_li)
    for i in range(show_start, show_end+1):
        if i == current_page:
            li_tag = '
{0}
'.format(i)
        else:
            li_tag = '
{0}
'.format(i)
        page_html_list.append(li_tag)

    # 加下一页
    if current_page == total_page:
        next_li = '
下一页
'
    else:
        next_li = '
下一页
'.format(current_page+1)
    page_html_list.append(next_li)

    # 加尾页
    page_end_li = '
尾页
'.format(total_page)
    page_html_list.append(page_end_li)

    page_html = "".join(page_html_list)

    return render(request, "user_list.html", {"user_list": user_list, "page_html": page_html})

2、封装可重用版

class Pagination(object):
    def __init__(self, current_page, total_count, base_url, per_page=10, max_show=11):
        """
        :param current_page: 当前页
        :param total_count: 数据库中数据总数
        :param per_page: 每页显示多少条数据
        :param max_show: 最多显示多少页
        """
        try:
            current_page = int(current_page)
        except Exception as e:
            current_page = 1

        self.current_page = current_page
        self.total_count = total_count
        self.base_url = base_url
        self.per_page = per_page
        self.max_show = max_show

        # 总页码
        total_page, more = divmod(total_count, per_page)
        if more:
            total_page += 1

        half_show = int((max_show - 1) / 2)
        self.half_show = half_show
        self.total_page = total_page

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

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

    def page_html(self):

        if self.current_page <= self.half_show:
            show_start = 1
            show_end = self.max_show
        else:
            if self.current_page + self.half_show >= self.total_page:
                show_start = self.total_page - self.max_show
                show_end = self.total_page
            else:
                show_start = self.current_page - self.half_show
                show_end = self.current_page + self.half_show

                # 生成页面上显示的页码
        page_html_list = []
        # 加首页
        first_li = '
首页
'.format(self.base_url)
        page_html_list.append(first_li)
        # 加上一页
        if self.current_page == 1:
            prev_li = '
上一页
'
        else:
            prev_li = '
上一页
'.format(self.base_url, self.current_page - 1)
        page_html_list.append(prev_li)
        for i in range(show_start, show_end + 1):
            if i == self.current_page:
                li_tag = '
{1}
'.format(self.base_url, i)
            else:
                li_tag = '
{1}
'.format(self.base_url, i)
            page_html_list.append(li_tag)

        # 加下一页
        if self.current_page == self.total_page:
            next_li = '
下一页
'
        else:
            next_li = '
下一页
'.format(self.base_url, self.current_page + 1)
        page_html_list.append(next_li)

        # 加尾页
        page_end_li = '
尾页
'.format(self.base_url, self.total_page)
        page_html_list.append(page_end_li)

        return "".join(page_html_list)

3、封装重用版本views.py使用方法

def user_list(request):
    pager = Pagination(request.GET.get("page"), len(data), request.path_info)
    user_list = data[pager.start:pager.end]
    page_html = pager.page_html()
    return render(request, "user_list.html", {"user_list": user_list, "page_html": page_html})

二、Django内置分页

1、内置分页views.py部分

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})

2、内置分页HTML部分

"en">
    "UTF-8">
    



    {% for item in posts %}
        
{{ item }}
    {% endfor %}


class="pagination">
      <span class="step-links">
        {% if posts.has_previous %}
            <a href="?p={{ posts.previous_page_number }}">Previousa>
        {% endif %}
          <span class="current">
            Page {{ posts.number }} of {{ posts.paginator.num_pages }}.
          span>
          {% if posts.has_next %}
              <a href="?p={{ posts.next_page_number }}">Nexta>
          {% endif %}
      span>

div>
body>
html>