• django-分页


    分页

    一、Django内置分页

    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})

    views.py


    复制代码
    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})
    复制代码

    <!DOCTYPE html>
    <html>
    <head lang="en">
    <meta charset="UTF-8">
    <title></title>
    </head>
    <body>
    <ul>
    {% for item in posts %}
    <li>{{ item }}</li>
    {% endfor %}
    </ul>

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

    </div>
    </body>
    </html>

    Html


    复制代码
    <!DOCTYPE html>
    <html>
    <head lang="en">
        <meta charset="UTF-8">
        <title></title>
    </head>
    <body>
    <ul>
        {% for item in posts %}
            <li>{{ item }}</li>
        {% endfor %}
    </ul>
    
    <div class="pagination">
          <span class="step-links">
            {% if posts.has_previous %}
                <a href="?p={{ posts.previous_page_number }}">Previous</a>
            {% endif %}
              <span class="current">
                Page {{ posts.number }} of {{ posts.paginator.num_pages }}.
              </span>
              {% if posts.has_next %}
                  <a href="?p={{ posts.next_page_number }}">Next</a>
              {% endif %}
          </span>
    
    </div>
    </body>
    </html>
    复制代码

    from django.shortcuts import render
    from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger


    class CustomPaginator(Paginator):
    def __init__(self, current_page, max_pager_num, *args, **kwargs):
    """
    :param current_page: 当前页
    :param max_pager_num:最多显示的页码个数
    :param args:
    :param kwargs:
    :return:
    """
    self.current_page = int(current_page)
    self.max_pager_num = max_pager_num
    super(CustomPaginator, self).__init__(*args, **kwargs)

    def page_num_range(self):
    # 当前页面
    # self.current_page
    # 总页数
    # self.num_pages
    # 最多显示的页码个数
    # self.max_pager_num
    print(1)
    if self.num_pages < self.max_pager_num:
    return range(1, self.num_pages + 1)
    print(2)
    part = int(self.max_pager_num / 2)
    if self.current_page - part < 1:
    return range(1, self.max_pager_num + 1)
    print(3)
    if self.current_page + part > self.num_pages:
    return range(self.num_pages + 1 - self.max_pager_num, self.num_pages + 1)
    print(4)
    return range(self.current_page - part, self.current_page + part + 1)


    L = []
    for i in range(999):
    L.append(i)

    def index(request):
    current_page = request.GET.get('p')
    paginator = CustomPaginator(current_page, 11, 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})

    扩展内置分页:views.py


    复制代码
    from django.shortcuts import render
    from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
    
    
    class CustomPaginator(Paginator):
        def __init__(self, current_page, max_pager_num, *args, **kwargs):
            """
            :param current_page: 当前页
            :param max_pager_num:最多显示的页码个数
            :param args:
            :param kwargs:
            :return:
            """
            self.current_page = int(current_page)
            self.max_pager_num = max_pager_num
            super(CustomPaginator, self).__init__(*args, **kwargs)
    
        def page_num_range(self):
            # 当前页面
            # self.current_page
            # 总页数
            # self.num_pages
            # 最多显示的页码个数
            # self.max_pager_num
            print(1)
            if self.num_pages < self.max_pager_num:
                return range(1, self.num_pages + 1)
            print(2)
            part = int(self.max_pager_num / 2)
            if self.current_page - part < 1:
                return range(1, self.max_pager_num + 1)
            print(3)
            if self.current_page + part > self.num_pages:
                return range(self.num_pages + 1 - self.max_pager_num, self.num_pages + 1)
            print(4)
            return range(self.current_page - part, self.current_page + part + 1)
    
    
    L = []
    for i in range(999):
        L.append(i)
    
    def index(request):
        current_page = request.GET.get('p')
        paginator = CustomPaginator(current_page, 11, 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})
    复制代码

    <!DOCTYPE html>
    <html>
    <head lang="en">
    <meta charset="UTF-8">
    <title></title>
    </head>
    <body>

    <ul>
    {% for item in posts %}
    <li>{{ item }}</li>
    {% endfor %}
    </ul>

    <div class="pagination">
    <span class="step-links">
    {% if posts.has_previous %}
    <a href="?p={{ posts.previous_page_number }}">Previous</a>
    {% endif %}

    {% for i in posts.paginator.page_num_range %}
    <a href="?p={{ i }}">{{ i }}</a>
    {% endfor %}

    {% if posts.has_next %}
    <a href="?p={{ posts.next_page_number }}">Next</a>
    {% endif %}
    </span>

    <span class="current">
    Page {{ posts.number }} of {{ posts.paginator.num_pages }}.
    </span>

    </div>
    </body>
    </html>

    扩展内置分页:Html


    复制代码
    <!DOCTYPE html>
    <html>
    <head lang="en">
        <meta charset="UTF-8">
        <title></title>
    </head>
    <body>
    
    <ul>
        {% for item in posts %}
            <li>{{ item }}</li>
        {% endfor %}
    </ul>
    
    <div class="pagination">
    <span class="step-links">
    {% if posts.has_previous %}
        <a href="?p={{ posts.previous_page_number }}">Previous</a>
    {% endif %}
    
        {% for i in posts.paginator.page_num_range %}
            <a href="?p={{ i }}">{{ i }}</a>
        {% endfor %}
    
        {% if posts.has_next %}
            <a href="?p={{ posts.next_page_number }}">Next</a>
        {% endif %}
    </span>
    
    <span class="current">
    Page {{ posts.number }} of {{ posts.paginator.num_pages }}.
    </span>
    
    </div>
    </body>
    </html>
    复制代码

    二、自定义分页

    分页功能在每个网站都是必要的,对于分页来说,其实就是根据用户的输入计算出应该在数据库表中的起始位置。

    1、设定每页显示数据条数

    2、用户输入页码(第一页、第二页...)

    3、根据设定的每页显示条数和当前页码,计算出需要取数据表的起始位置

    4、在数据表中根据起始位置取值,页面上输出数据


    需求又来了,需要在页面上显示分页的页面。如:[上一页][1][2][3][4][5][下一页]

    1、设定每页显示数据条数

    2、用户输入页码(第一页、第二页...)

    3、设定显示多少页号

    4、获取当前数据总条数

    5、根据设定显示多少页号和数据总条数计算出,总页数

    6、根据设定的每页显示条数和当前页码,计算出需要取数据表的起始位置

    7、在数据表中根据起始位置取值,页面上输出数据

    8、输出分页html,如:[上一页][1][2][3][4][5][下一页]

    #!/usr/bin/env python
    # _*_coding:utf-8_*_
    from django.utils.safestring import mark_safe
     
    class PageInfo(object):
        def __init__(self,current,totalItem,peritems=5):
            self.__current=current
            self.__peritems=peritems
            self.__totalItem=totalItem
        def From(self):
            return (self.__current-1)*self.__peritems
        def To(self):
            return self.__current*self.__peritems
        def TotalPage(self):  #总页数
            result=divmod(self.__totalItem,self.__peritems)
            if result[1]==0:
                return result[0]
            else:
                return result[0]+1
     
    def Custompager(baseurl,currentPage,totalpage):  #基础页,当前页,总页数
        perPager=11
        #总页数<11
        #0 -- totalpage
        #总页数>11
            #当前页大于5 currentPage-5 -- currentPage+5
                #currentPage+5是否超过总页数,超过总页数,end就是总页数
            #当前页小于5 0 -- 11
        begin=0
        end=0
        if totalpage <= 11:
            begin=0
            end=totalpage
        else:
            if currentPage>5:
                begin=currentPage-5
                end=currentPage+5
                if end > totalpage:
                    end=totalpage
            else:
                begin=0
                end=11
        pager_list=[]
        if currentPage<=1:
            first="<a href=''>首页</a>"
        else:
            first="<a href='%s%d'>首页</a>" % (baseurl,1)
        pager_list.append(first)
     
        if currentPage<=1:
            prev="<a href=''>上一页</a>"
        else:
            prev="<a href='%s%d'>上一页</a>" % (baseurl,currentPage-1)
        pager_list.append(prev)
     
        for i in range(begin+1,end+1):
            if i == currentPage:
                temp="<a href='%s%d' class='selected'>%d</a>" % (baseurl,i,i)
            else:
                temp="<a href='%s%d'>%d</a>" % (baseurl,i,i)
            pager_list.append(temp)
        if currentPage>=totalpage:
            next="<a href='#'>下一页</a>"
        else:
            next="<a href='%s%d'>下一页</a>" % (baseurl,currentPage+1)
        pager_list.append(next)
        if currentPage>=totalpage:
            last="<a href=''>末页</a>"
        else:
            last="<a href='%s%d'>末页</a>" % (baseurl,totalpage)
        pager_list.append(last)
        result=''.join(pager_list)
        return mark_safe(result)   #把字符串转成html语言

    复制代码
    #!/usr/bin/env python
    # _*_coding:utf-8_*_
    from django.utils.safestring import mark_safe
     
    class PageInfo(object):
        def __init__(self,current,totalItem,peritems=5):
            self.__current=current
            self.__peritems=peritems
            self.__totalItem=totalItem
        def From(self):
            return (self.__current-1)*self.__peritems
        def To(self):
            return self.__current*self.__peritems
        def TotalPage(self):  #总页数
            result=divmod(self.__totalItem,self.__peritems)
            if result[1]==0:
                return result[0]
            else:
                return result[0]+1
     
    def Custompager(baseurl,currentPage,totalpage):  #基础页,当前页,总页数
        perPager=11
        #总页数<11
        #0 -- totalpage
        #总页数>11
            #当前页大于5 currentPage-5 -- currentPage+5
                #currentPage+5是否超过总页数,超过总页数,end就是总页数
            #当前页小于5 0 -- 11
        begin=0
        end=0
        if totalpage <= 11:
            begin=0
            end=totalpage
        else:
            if currentPage>5:
                begin=currentPage-5
                end=currentPage+5
                if end > totalpage:
                    end=totalpage
            else:
                begin=0
                end=11
        pager_list=[]
        if currentPage<=1:
            first="<a href=''>首页</a>"
        else:
            first="<a href='%s%d'>首页</a>" % (baseurl,1)
        pager_list.append(first)
     
        if currentPage<=1:
            prev="<a href=''>上一页</a>"
        else:
            prev="<a href='%s%d'>上一页</a>" % (baseurl,currentPage-1)
        pager_list.append(prev)
     
        for i in range(begin+1,end+1):
            if i == currentPage:
                temp="<a href='%s%d' class='selected'>%d</a>" % (baseurl,i,i)
            else:
                temp="<a href='%s%d'>%d</a>" % (baseurl,i,i)
            pager_list.append(temp)
        if currentPage>=totalpage:
            next="<a href='#'>下一页</a>"
        else:
            next="<a href='%s%d'>下一页</a>" % (baseurl,currentPage+1)
        pager_list.append(next)
        if currentPage>=totalpage:
            last="<a href=''>末页</a>"
        else:
            last="<a href='%s%d'>末页</a>" % (baseurl,totalpage)
        pager_list.append(last)
        result=''.join(pager_list)
        return mark_safe(result)   #把字符串转成html语言
    复制代码

    总结,分页时需要做三件事:

    • 创建处理分页数据的类
    • 根据分页数据获取数据
    • 输出分页HTML,即:[上一页][1][2][3][4][5][下一页]

    分页中前端实现页面跳转的js:location.href=base基础路径+val页码数

    逆风的方向最适合飞翔,我不怕千万人阻挡,只怕自己投降。
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  • 原文地址:https://www.cnblogs.com/daemon-czk/p/9813755.html
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