编程 Python

Python Django 添加首页尾页上一页下一页代码实例

Posted in Python onAugust 21, 2019

添加首页和尾页：

views.py：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 从 URL 中取参数
  page_num = request.GET.get("page")
  print(page_num, type(page_num))
  page_num = int(page_num) 
  # 定义两个变量保存数据从哪儿取到哪儿
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 书籍总数
  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显示
  total_page, m = divmod(total_count, per_page) 
  # 页面上最多展示的页码
  max_page = 11
  half_max_page = max_page // 2
 
  # 页面上展示的页码的开始页
  page_start = page_num - half_max_page
  # 页面上展示的页码的结束页
  page_end = page_num + half_max_page 
  # 如果当前页减一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果当前页加一半比总页码还大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  # 如果还有数据
  if m:
    total_page += 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分页代码
  html_list = [] 
  # 添加首页按钮
  html_list.append('<li><a href="/books/?page=1" rel="external nofollow" >首页</a></li>')
  # 展示的页码
  for i in range(page_start, page_end + 1):
    tmp = '<li><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    html_list.append(tmp) 
  # 添加尾页按钮
  html_list.append('<li><a href="/books/?page={}" rel="external nofollow" >尾页</a></li>'.format(total_page)) 
  page_html = "".join(html_list) # 拼接 html 的分页代码 
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

book_list.html：

<!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" rel="external nofollow" rel="external nofollow" >
</head>
<body> 
<div class="container"> 
  <table class="table table-bordered">
    <thead>
    <tr>
      <th>序号</th>
      <th>id</th>
      <th>书名</th>
    </tr>
    </thead>
    <tbody>
    {% for book in books %}
      <tr>
        <td>{{ forloop.counter }}</td>
        <td>{{ book.id }}</td>
        <td>{{ book.title }}</td>
      </tr>
    {% endfor %}
    </tbody>
  </table> 
  <nav aria-label="Page navigation">
    <ul class="pagination">
      <li>
        {{ page_html|safe }}
      </li>
    </ul>
  </nav>
</div> 
</body>
</html>

运行结果：

Python Django 添加首页尾页上一页下一页代码实例

views.py：

from django.shortcuts import render
from app01 import models 
def book_list(request):
  # 从 URL 中取参数
  page_num = request.GET.get("page")
  print(page_num, type(page_num))
  page_num = int(page_num) 
  # 定义两个变量保存数据从哪儿取到哪儿
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 书籍总数
  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显示
  total_page, m = divmod(total_count, per_page) 
  # 页面上最多展示的页码
  max_page = 11
  half_max_page = max_page // 2 
  # 页面上展示的页码的开始页
  page_start = page_num - half_max_page
  # 页面上展示的页码的结束页
  page_end = page_num + half_max_page 
  # 如果当前页减一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果当前页加一半比总页码还大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  # 如果还有数据
  if m:
    total_page += 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分页代码
  html_list = [] 
  # 添加首页按钮
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首页</a></li>') 
  # 如果是第一页，就没有上一页
  if page_num <= 1:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1))
  else:
    # 加一个上一页的标签
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1)) 
  # 展示的页码
  for i in range(page_start, page_end + 1):
    # 给当前页添加 active
    if i == page_num:
      tmp = '<li class="active"><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    else:
      tmp = '<li><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    html_list.append(tmp) 
  # 如果是最后一页，就没有下一页
  if page_num >= total_page:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>')
  else:
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>'.format(page_num+1)) 
  # 添加尾页按钮
  html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >尾页</a></li>'.format(total_page))
 
  page_html = "".join(html_list) # 拼接 html 的分页代码
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

book_list.html：

<!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" rel="external nofollow" rel="external nofollow" >
</head>
<body> 
<div class="container"> 
  <table class="table table-bordered">
    <thead>
    <tr>
      <th>序号</th>
      <th>id</th>
      <th>书名</th>
    </tr>
    </thead>
    <tbody>
    {% for book in books %}
      <tr>
        <td>{{ forloop.counter }}</td>
        <td>{{ book.id }}</td>
        <td>{{ book.title }}</td>
      </tr>
    {% endfor %} 
    </tbody>
  </table>
  <nav aria-label="Page navigation">
    <ul class="pagination">
      <li>
        {{ page_html|safe }}
      </li>
    </ul>
  </nav> 
</div>
</body>
</html>

运行结果：

Python Django 添加首页尾页上一页下一页代码实例

后续改进：

处理用户传给 url 的 page 参数异常的值的情况

例如：

访问，http://127.0.0.1:8888/book_list/?page=a

访问，http://127.0.0.1:8888/book_list/?page=-1

都会出错

改进：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 从 URL 中取参数
  page_num = request.GET.get("page")
  print(page_num, type(page_num)) # page_num 为 str 类型
  # 书籍总数
  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显示
  total_page, m = divmod(total_count, per_page) 
  # 如果还有数据
  if m:
    total_page += 1
  try:
    page_num = int(page_num)
    # 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
    # 如果输入的页码数小于 1，则返回第一页
    if page_num < 1:
      page_num = 1
  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
  # 定义两个变量保存数据从哪儿取到哪儿
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 页面上最多展示的页码
  max_page = 11
  half_max_page = max_page // 2
  # 页面上展示的页码的开始页
  page_start = page_num - half_max_page
  # 页面上展示的页码的结束页
  page_end = page_num + half_max_page 
  # 如果当前页减一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果当前页加一半比总页码还大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分页代码
  html_list = [] 
  # 添加首页按钮
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首页</a></li>') 
  # 如果是第一页，就没有上一页
  if page_num <= 1:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1))
  else:
    # 加一个上一页的标签
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1))
   # 展示的页码
  for i in range(page_start, page_end + 1):
    # 给当前页添加 active
    if i == page_num:
      tmp = '<li class="active"><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    else:
      tmp = '<li><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    html_list.append(tmp) 
  # 如果是最后一页，就没有下一页
  if page_num >= total_page:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>')
  else:
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>'.format(page_num+1)) 
  # 添加尾页按钮
  html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >尾页</a></li>'.format(total_page))
 
  page_html = "".join(html_list) # 拼接 html 的分页代码
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

如果数据库中的数据数少于 max_page，则会显示负数的页数

例如数据库中只有 21 条数据：

Python Django 添加首页尾页上一页下一页代码实例

改进：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 从 URL 中取参数
  page_num = request.GET.get("page")
  print(page_num, type(page_num)) # page_num 为 str 类型 
  # 书籍总数
  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显示
  total_page, m = divmod(total_count, per_page) 
  # 如果还有数据
  if m:
    total_page += 1
  try:
    page_num = int(page_num)
    # 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
    # 如果输入的页码数小于 1，则返回第一页
    if page_num < 1:
      page_num = 1
  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 
  # 定义两个变量保存数据从哪儿取到哪儿
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 页面上最多展示的页码
  max_page = 11
  # 如果总页码数小于页面上最多展示的页码
  if total_page < max_page:
    max_page = total_page
  half_max_page = max_page // 2 
  # 页面上展示的页码的开始页
  page_start = page_num - half_max_page
  # 页面上展示的页码的结束页
  page_end = page_num + half_max_page 
  # 如果当前页减一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果当前页加一半比总页码还大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分页代码
  html_list = [] 
  # 添加首页按钮
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首页</a></li>') 
  # 如果是第一页，就没有上一页
  if page_num <= 1:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1))
  else:
    # 加一个上一页的标签
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">«</span></a></li>'.format(page_num-1))
  # 展示的页码
  for i in range(page_start, page_end + 1):
    # 给当前页添加 active
    if i == page_num:
      tmp = '<li class="active"><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    else:
      tmp = '<li><a href="/book_list/?page={0}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >{0}</a></li>'.format(i)
    html_list.append(tmp) 
  # 如果是最后一页，就没有下一页
  if page_num >= total_page:
    html_list.append('<li class="disabled"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>')
  else:
    html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><span aria-hidden="true">»</span></a></li>'.format(page_num+1)) 
  # 添加尾页按钮
  html_list.append('<li><a href="/book_list/?page={}" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >尾页</a></li>'.format(total_page)) 
  page_html = "".join(html_list) # 拼接 html 的分页代码
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

运行结果：

Python Django 添加首页尾页上一页下一页代码实例

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持三水点靠木。

Python Django 添加首页尾页上一页下一页代码实例

- Author -

Sch01aR#

声明：登载此文出于传递更多信息之目的，并不意味着赞同其观点或证实其描述。

Python 相关文章推荐

python实现从字典中删除元素的方法

May 04 Python

Python常用内置模块之xml模块(详解)

May 23 Python

Python基于Flask框架配置依赖包信息的项目迁移部署

Mar 02 Python

django 发送手机验证码的示例代码

Apr 25 Python

python调用OpenCV实现人脸识别功能

May 25 Python

Python数据持久化shelve模块用法分析

Jun 29 Python

python机器学习之KNN分类算法

Aug 29 Python

django 捕获异常和日志系统过程详解

Jul 18 Python

python爬虫解决验证码的思路及示例

Aug 01 Python

Python 闭包，函数分隔作用域，nonlocal声明非局部变量操作示例

Oct 14 Python

Python Celery多队列配置代码实例

Nov 22 Python

python用pip install时安装失败的一系列问题及解决方法

Feb 24 Python

Python Django 简单分页的实现代码解析

Aug 21 #Python

Django项目之Elasticsearch搜索引擎的实例

Aug 21 #Python

python爬虫豆瓣网的模拟登录实现

Aug 21 #Python

Python Django 页面上展示固定的页码数实现代码

Aug 21 #Python

详解Python利用random生成一个列表内的随机数

Aug 21 #Python

Python Django 封装分页成通用的模块详解

Aug 21 #Python

Django之编辑时根据条件跳转回原页面的方法

Aug 21 #Python