分页

自定义分页

稳扎稳打版

def book(request):
    # 从URL取参数（访问的页码）
    page_num = request.GET.get("page")
    try:
        # 将取出的page转换为int类型
        page_num = int(page_num)
    except Exception as e:
        # 当输入的页码不是正经数字的时候 默认返回第一页的数据
        page_num = 1
 
    # 数据库总数据是多少条
    total_count = models.Book.objects.all().count()
    # 每一页显示多少条数据
    per_page = 10
 
    # 总共需要多少页码来展示
    total_page, m = divmod(total_count, per_page)
    if m:
        total_page += 1
 
    # 如果输入的页码数超过了最大的页码数，默认返回最后一页
    if page_num > total_page:
        page_num = total_page
    # 定义两个变量从哪里开始到哪里结束
    data_start = (page_num - 1) * 10
    data_end = page_num * 10
 
    # 页面上总共展示多少页码
    max_page = 11
    if total_page < max_page:
        max_page = total_page
    # 把从URL中获取的page_num 当做是显示页面的中间值， 那么展示的便是当前page_num 的前五页和后后五页
    half_max_page = max_page // 2
    # 根据展示的总页码算出页面上展示的页码从哪儿开始
    page_start = page_num - half_max_page
    # 根据展示的总页码算出页面上展示的页码到哪儿结束
    page_end = page_num + half_max_page
    # 如果当前页减一半 比1还小, 不然页面上会显示负数的页码
    if page_start <= 1:
        page_start = 1
        page_end = max_page
    # 如果 当前页 加 一半 比总页码数还大， 不然页面上会显示比总页码还大的多余页码
    if page_end >= total_page:
        page_end = total_page
        page_start = total_page - max_page + 1
 
    # 从数据库取值， 并按照起始数据到结束数据展示
    all_book = models.Book.objects.all()[data_start:data_end]
    # 自己拼接分页的HTML代码
    html_str_list = []
    # # 加上首页
    html_str_list.append('<li><a href="/book/?page=1">首页</a></li>')
    # 断一下 如果是第一页，就没有上一页
    if page_num <= 1:
        html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">&laquo;</span></a></li>')
    else:
        # 不是第一页，就加一个上一页的标签
        html_str_list.append('<li><a href="/book/?page={}"><span aria-hidden="true">&laquo;</span></a></li>'.format(page_num - 1))
    for i in range(page_start, page_end + 1):
        # 如果是当前页就加一个active样式类
        if i == page_num:
            tmp = '<li class="active"><a href="/book/?page={0}">{0}</a></li>'.format(i)
        else:
            tmp = '<li><a href="/book/?page={0}">{0}</a></li>'.format(i)
        html_str_list.append(tmp)
    # 判断，如果是最后一页，就没有下一页
    if page_num >= total_page:
        html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">&raquo;</span></a></li>')
    else:
        # 不是最后一页， 就加一个下一页标签
        html_str_list.append('<li><a href="/book/?page={}"><span aria-hidden="true">&raquo;</span></a></li>'.format(page_num + 1))
    # 加上尾页
    html_str_list.append('<li><a href="/book/?page={}">尾页</a></li>'.format(total_page))
    page_html = "".join(html_str_list)
    return render(request, "book.html", {"all_book":all_book, "page_html":page_html})

稳扎稳打版

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>书籍列表</title>
    <link rel="stylesheet" href="/static/bootstrap/css/bootstrap.min.css">
</head>
<body>
<div class="container">
<table class="table table-bordered">
    <thead>
        <tr>
            <th>序列号</th>
            <th>ID值</th>
            <th>书名</th>
            <th>时间</th>
        </tr>
        {% for book in all_book %}
        <tr>
            <td>{{ forloop.counter }}</td>
            <td>{{ book.id }}</td>
            <td>{{ book.name }}</td>
            <td>{{ book.date }}</td>
        </tr>
        {% endfor %}
    </thead>
</table>
<nav aria-label="Page navigation">
  <ul class="pagination">
      {{ page_html|safe }}
  </ul>
</nav>
</div>
</body>
</html>

book.html

封装保存版

class Page(object):
    def __init__(self, page_num, total_count, url_prefix, per_page=10, max_page=11):
        """
        :param page_num: 当前页码数
        :param total_count: 数据总数
        :param url_prefix: a标签href的前缀
        :param per_page: 每页显示多少条数据
        :param max_page: 页面上最多显示几个页码
        """
        self.url_prefix = url_prefix
        self.max_page = max_page
        # 总共需要多少页码来展示
        total_page, m = divmod(total_count, per_page)
        if m:
            total_page += 1
        self.total_page = total_page
        try:
            # 将取出的page转换为int类型
            page_num = int(page_num)
        except Exception as e:
            # 当输入的页码不是正经数字的时候 默认返回第一页的数据
            page_num = 1
        # 如果输入的页码数超过了最大的页码数，默认返回最后一页
        if page_num > total_page:
            page_num = total_page
        self.page_num = page_num
        # 定义两个变量保存数据从哪儿取到哪儿
        self.data_start = (page_num - 1) * 10
        self.data_end = page_num * 10
 
        # 页面上总共展示多少页码
        if total_page < self.max_page:
            self.max_page = total_page
        half_max_page = self.max_page // 2
        # 页面上展示的页码从哪儿开始
        page_start = page_num - half_max_page
        # 页面上展示的页码到哪儿结束
        page_end = page_num + half_max_page
        # 如果当前页减一半 比1还小, 不然页面上会显示负数的页码
        if page_start <= 1:
            page_start = 1
            page_end = self.max_page
        # 如果 当前页 加 一半 比总页码数还大， 不然页面上会显示比总页码还大的多余页码
        if page_end >= total_page:
            page_end = total_page
            page_start = total_page - self.max_page + 1
        self.page_start = page_start
        self.page_end = page_end
    @property
    def start(self):
        return self.data_start
    @property
    def end(self):
        return self.data_end
    def page_html(self):
        # 自己拼接分页的HTML代码
        html_str_list = []
        # # 加上首页
        html_str_list.append('<li><a href="{}?page=1">首页</a></li>'.format(self.url_prefix))
        # 断一下 如果是第一页，就没有上一页
        if self.page_num <= 1:
            html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">&laquo;</span></a></li>')
        else:
            # 不是第一页，就加一个上一页的标签
            html_str_list.append('<li><a href="{}?page={}"><span aria-hidden="true">&laquo;</span></a></li>'.format(self.url_prefix, self.page_num - 1))
        for i in range(self.page_start, self.page_end + 1):
            # 如果是当前页就加一个active样式类
            if i == self.page_num:
                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)
            html_str_list.append(tmp)
        # 判断，如果是最后一页，就没有下一页
        if self.page_num >= self.total_page:
            html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">&raquo;</span></a></li>')
        else:
            # 不是最后一页， 就加一个下一页标签
            html_str_list.append('<li><a href="{}?page={}"><span aria-hidden="true">&raquo;</span></a></li>'.format(self.url_prefix, self.page_num + 1))
        # 加上尾页
        html_str_list.append('<li><a href="{}?page={}">尾页</a></li>'.format(self.url_prefix, self.total_page))
        page_html = "".join(html_str_list)
        return page_html

封装保存版

def publisher(request):
    page_num = request.GET.get("page")
    total_count = models.Publisher.objects.all().count()
    # 调用封装的Page类，传入相应的参数
    page_obj = Page(page_num, total_count, url_prefix="/publisher/", per_page=10, max_page=11)
    all_publisher = models.Publisher.objects.all()[page_obj.start:page_obj.end]
    page_html = page_obj.page_html()
    return render(request, "publisher.html", {"publisher": all_publisher, "page_html": page_html})

封装版使用指南

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>图书列表</title>
    <link rel="stylesheet" href="/static/bootstrap/css/bootstrap.min.css">
</head>
<body>
<div class="container">
    <table class="table table-bordered">
        <thead>
        <tr>
            <td>序列号</td>
            <td>ID值</td>
            <td>出版社</td>
            <td>时间</td>
        </tr>
        </thead>
        <tbody>
        {% for pub in publisher %}
            <tr>
                <th>{{ forloop.counter }}</th>
                <th>{{ pub.id }}</th>
                <th>{{ pub.name }}</th>
                <th>{{ pub.date }}</th>
            </tr>
        {% endfor %}
        </tbody>
    </table>
    <nav aria-label="Page navigation">
        <ul class="pagination">
            {{ page_html|safe }}
        </ul>
    </nav>
</div>
</body>
</html>