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Python Django 添加首頁尾頁上一頁下一頁代碼實(shí)例

更新時(shí)間：2019年08月21日 11:19:18 作者：Sch01aR#

這篇文章主要介紹了Python Django 添加首頁尾頁上一頁下一頁代碼實(shí)例,文中通過示例代碼介紹的非常詳細(xì)，對(duì)大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價(jià)值,需要的朋友可以參考下

添加首頁和尾頁：

views.py：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 從 URL 中取參數(shù)
  page_num = request.GET.get("page")
  print(page_num, type(page_num))
  page_num = int(page_num) 
  # 定義兩個(gè)變量保存數(shù)據(jù)從哪兒取到哪兒
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 書籍總數(shù)
  total_count = models.Book.objects.all().count() 
  # 每一頁顯示多少條數(shù)據(jù)
  per_page = 10
  # 總共需要多少頁碼來顯示
  total_page, m = divmod(total_count, per_page) 
  # 頁面上最多展示的頁碼
  max_page = 11
  half_max_page = max_page // 2
 
  # 頁面上展示的頁碼的開始頁
  page_start = page_num - half_max_page
  # 頁面上展示的頁碼的結(jié)束頁
  page_end = page_num + half_max_page 
  # 如果當(dāng)前頁減一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果當(dāng)前頁加一半比總頁碼還大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  # 如果還有數(shù)據(jù)
  if m:
    total_page += 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分頁代碼
  html_list = [] 
  # 添加首頁按鈕
  html_list.append('<li><a href="/books/?page=1" rel="external nofollow" >首頁</a></li>')
  # 展示的頁碼
  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) 
  # 添加尾頁按鈕
  html_list.append('<li><a href="/books/?page={}" rel="external nofollow" >尾頁</a></li>'.format(total_page)) 
  page_html = "".join(html_list) # 拼接 html 的分頁代碼 
  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>書籍列表</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>序號(hào)</th>
      <th>id</th>
      <th>書名</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>

運(yùn)行結(jié)果：

views.py：

from django.shortcuts import render
from app01 import models 
def book_list(request):
  # 從 URL 中取參數(shù)
  page_num = request.GET.get("page")
  print(page_num, type(page_num))
  page_num = int(page_num) 
  # 定義兩個(gè)變量保存數(shù)據(jù)從哪兒取到哪兒
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 書籍總數(shù)
  total_count = models.Book.objects.all().count() 
  # 每一頁顯示多少條數(shù)據(jù)
  per_page = 10 
  # 總共需要多少頁碼來顯示
  total_page, m = divmod(total_count, per_page) 
  # 頁面上最多展示的頁碼
  max_page = 11
  half_max_page = max_page // 2 
  # 頁面上展示的頁碼的開始頁
  page_start = page_num - half_max_page
  # 頁面上展示的頁碼的結(jié)束頁
  page_end = page_num + half_max_page 
  # 如果當(dāng)前頁減一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果當(dāng)前頁加一半比總頁碼還大
  if page_end > total_page:
    page_end = total_page
    page_start = total_page - max_page + 1 
  # 如果還有數(shù)據(jù)
  if m:
    total_page += 1 
  all_book = models.Book.objects.all()[data_start:data_end] 
  # 拼接 html 的分頁代碼
  html_list = [] 
  # 添加首頁按鈕
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首頁</a></li>') 
  # 如果是第一頁，就沒有上一頁
  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:
    # 加一個(gè)上一頁的標(biāo)簽
    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)) 
  # 展示的頁碼
  for i in range(page_start, page_end + 1):
    # 給當(dāng)前頁添加 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) 
  # 如果是最后一頁，就沒有下一頁
  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)) 
  # 添加尾頁按鈕
  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" >尾頁</a></li>'.format(total_page))
 
  page_html = "".join(html_list) # 拼接 html 的分頁代碼
  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>書籍列表</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>序號(hào)</th>
      <th>id</th>
      <th>書名</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>

運(yùn)行結(jié)果：

后續(xù)改進(jìn)：

處理用戶傳給 url 的 page 參數(shù)異常的值的情況

例如：

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

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

都會(huì)出錯(cuò)

改進(jìn)：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 從 URL 中取參數(shù)
  page_num = request.GET.get("page")
  print(page_num, type(page_num)) # page_num 為 str 類型
  # 書籍總數(shù)
  total_count = models.Book.objects.all().count() 
  # 每一頁顯示多少條數(shù)據(jù)
  per_page = 10 
  # 總共需要多少頁碼來顯示
  total_page, m = divmod(total_count, per_page) 
  # 如果還有數(shù)據(jù)
  if m:
    total_page += 1
  try:
    page_num = int(page_num)
    # 如果輸入的頁碼數(shù)超過了最大的頁碼數(shù)，默認(rèn)返回最后一頁
    if page_num > total_page:
      page_num = total_page
    # 如果輸入的頁碼數(shù)小于 1，則返回第一頁
    if page_num < 1:
      page_num = 1
  except Exception as e:
    # 當(dāng)輸入的頁碼不是正經(jīng)數(shù)字的時(shí)候 默認(rèn)返回第一頁的數(shù)據(jù)
    page_num = 1
  # 定義兩個(gè)變量保存數(shù)據(jù)從哪兒取到哪兒
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 頁面上最多展示的頁碼
  max_page = 11
  half_max_page = max_page // 2
  # 頁面上展示的頁碼的開始頁
  page_start = page_num - half_max_page
  # 頁面上展示的頁碼的結(jié)束頁
  page_end = page_num + half_max_page 
  # 如果當(dāng)前頁減一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果當(dāng)前頁加一半比總頁碼還大
  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 的分頁代碼
  html_list = [] 
  # 添加首頁按鈕
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首頁</a></li>') 
  # 如果是第一頁，就沒有上一頁
  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:
    # 加一個(gè)上一頁的標(biāo)簽
    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))
   # 展示的頁碼
  for i in range(page_start, page_end + 1):
    # 給當(dāng)前頁添加 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) 
  # 如果是最后一頁，就沒有下一頁
  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)) 
  # 添加尾頁按鈕
  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" >尾頁</a></li>'.format(total_page))
 
  page_html = "".join(html_list) # 拼接 html 的分頁代碼
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

如果數(shù)據(jù)庫中的數(shù)據(jù)數(shù)少于 max_page，則會(huì)顯示負(fù)數(shù)的頁數(shù)

例如數(shù)據(jù)庫中只有 21 條數(shù)據(jù)：

改進(jìn)：

from django.shortcuts import render
from app01 import models
def book_list(request):
  # 從 URL 中取參數(shù)
  page_num = request.GET.get("page")
  print(page_num, type(page_num)) # page_num 為 str 類型 
  # 書籍總數(shù)
  total_count = models.Book.objects.all().count() 
  # 每一頁顯示多少條數(shù)據(jù)
  per_page = 10 
  # 總共需要多少頁碼來顯示
  total_page, m = divmod(total_count, per_page) 
  # 如果還有數(shù)據(jù)
  if m:
    total_page += 1
  try:
    page_num = int(page_num)
    # 如果輸入的頁碼數(shù)超過了最大的頁碼數(shù)，默認(rèn)返回最后一頁
    if page_num > total_page:
      page_num = total_page
    # 如果輸入的頁碼數(shù)小于 1，則返回第一頁
    if page_num < 1:
      page_num = 1
  except Exception as e:
    # 當(dāng)輸入的頁碼不是正經(jīng)數(shù)字的時(shí)候 默認(rèn)返回第一頁的數(shù)據(jù)
    page_num = 1 
  # 定義兩個(gè)變量保存數(shù)據(jù)從哪兒取到哪兒
  data_start = (page_num - 1) * 10
  data_end = page_num * 10 
  # 頁面上最多展示的頁碼
  max_page = 11
  # 如果總頁碼數(shù)小于頁面上最多展示的頁碼
  if total_page < max_page:
    max_page = total_page
  half_max_page = max_page // 2 
  # 頁面上展示的頁碼的開始頁
  page_start = page_num - half_max_page
  # 頁面上展示的頁碼的結(jié)束頁
  page_end = page_num + half_max_page 
  # 如果當(dāng)前頁減一半比 1 小
  if page_start <= 1:
    page_start = 1
    page_end = max_page
  # 如果當(dāng)前頁加一半比總頁碼還大
  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 的分頁代碼
  html_list = [] 
  # 添加首頁按鈕
  html_list.append('<li><a href="/book_list/?page=1" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首頁</a></li>') 
  # 如果是第一頁，就沒有上一頁
  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:
    # 加一個(gè)上一頁的標(biāo)簽
    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))
  # 展示的頁碼
  for i in range(page_start, page_end + 1):
    # 給當(dāng)前頁添加 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) 
  # 如果是最后一頁，就沒有下一頁
  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)) 
  # 添加尾頁按鈕
  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" >尾頁</a></li>'.format(total_page)) 
  page_html = "".join(html_list) # 拼接 html 的分頁代碼
  return render(request, "book_list.html", {"books": all_book, "page_html": page_html})

運(yùn)行結(jié)果：