Python之路【第三十二篇】:django 分頁器

時間 2020-05-10

標籤 python 之路第三十二篇 django 分頁欄目 Python 简体版

原文原文鏈接

Django的分頁器paginator

文件爲pageDemocss

models.pyhtml

from django.db import models

# Create your models here.
class Book(models.Model):
    title = models.CharField(max_length=32)
    price = models.DecimalField(decimal_places=2, max_digits=8)

views.pygit

from django.shortcuts import render

# Create your views here.
from .models import Book
from django.core.paginator import Paginator, EmptyPage
def index(request):
    '''
    批量導入:  #批量導入數據庫文件裏邊
    book_list = []
    for i in range(100):
        book = Book(title="book_%s"%i, price=i*i) #實例化一個book對象；
        book_list.append(book)                    #實例化出100個對象；
    Book.objects.bulk_create(book_list)           #批量插入
    return render(request, "index.html")
    :param request:
    :return:
    '''
    book_list = Book.objects.all()  #拿到全部書籍數據
    #分頁器
    paginator = Paginator(book_list, 8) #對誰分頁，一頁顯示多少條數據 總的分頁器對象
    print("count:",paginator.count)           #數據總數  打印：count:100
    print("num_pages",paginator.num_pages)    #總頁數　　　　　num_pages:13
    print("page_range",paginator.page_range)  #頁碼的列表 　　 page_range range(1,14)

    try: #page數字超了或者不在那個返回裏就會拋出一個EmptyPage的錯誤
        current_page_num = int(request.GET.get("page", 1))  #作成一個動態的效果。給它個默認值拿第一頁，不加1就會返回一個None。當前想要的第幾頁的數據
        current_page = paginator.page(current_page_num)     #拿到第幾頁的page對象。
        #顯示某一頁具體數據的兩種方式：
        print("object_list", current_page.object_list)
        for i in current_page:
            print(i)
    except EmptyPage as e:
        current_page=paginator.page(1)     #拿到第一頁的page對象
    return render(request, "index.html", locals())

index.html數據庫

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
    <ul>
        {% for book in current_page %} 
        <li>{{ book.title }}:{{ book.price }}</li> 
        {% endfor %}
    </ul>

    <nav aria-label="Page navigation">  //分頁的頁面
        <ul class="pagination">
            {% if current_page.has_previous %} //上一頁：當前頁碼-1 ---> href="?page={{current_page_num|add:-1}}或者下面這種寫法 ；判斷當前頁是否還有上一頁、下一頁
            <li><a href="?page={{ current_page.previous_page_number }}" aria-label="Previous"><span aria-hidden="true">上一頁</span></a></li>
            {% else %}
            <li class="disabled"><a href="" aria-label="Previous"><span aria-hidden="true">上一頁</span></a></li>  //沒有上一頁就不
            {% endif %}


            {% for item in paginator.page_range %}  //item爲數字  這裏不應寫死-->page_range
                {% if current_page_num == item %}
                    <li class="active"><a href="?page={{ item }}">{{ item }}</a></li>  //也當前頁碼匹配成功了，加個class="active" 一點擊誰顏色就會變深
                {% else %}
                    <li><a href="?page={{ item }}">{{ item }}</a></li>
                {% endif %}
            {% endfor %}

            {% if current_page.has_next %}
                <li><a href="?page={{ current_page.next_page_number }}" aria-label="Next"><span aria-hidden="true">下一頁</span></a></li>
            {% else %}
                <li class="disabled"><a href="" aria-label="Next"><span aria-hidden="true">下一頁</span></a></li>
            {% endif %}

        </ul>
    </nav>
</body>
</html>

改進版

viewsdjango

from django.shortcuts import render

# Create your views here.
from .models import Book
from django.core.paginator import Paginator, EmptyPage
def index(request):
    '''
    批量導入:
    book_list = []
    for i in range(100):
        book = Book(title="book_%s"%i, price=i*i)
        book_list.append(book)
    Book.objects.bulk_create(book_list)  #匹配插入
    return render(request, "index.html")
    :param request:
    :return:
    '''
    book_list = Book.objects.all()
    #分頁器
    paginator = Paginator(book_list, 3)
    print("count:",paginator.count)           #數據總數
    print("num_pages",paginator.num_pages)    #總頁數
    print("page_range",paginator.page_range)  #頁碼的列表

    current_page_num = int(request.GET.get("page", 1))
    if paginator.num_pages>11:
        if current_page_num-5 < 1:                     ##點一、二、三、四、5頁碼不動，點7開始顯示左5右5
            page_range = range(1, 12)
        elif current_page_num+5 > paginator.num_pages: #若是大於最大頁碼數
            page_range = range(paginator.num_pages-10, paginator.num_pages+1)
        else:
           
    else:
        current_page = paginator.page_range

    try:
        current_page_num = int(request.GET.get("page", 1))
        current_page = paginator.page(current_page_num)
        #顯示某一頁具體數據的兩種方式：
        print("object_list", current_page.object_list)
        for i in current_page:
            print(i)
    except EmptyPage as e:
        current_page=paginator.page(1)
    return render(request, "index.html", locals())

index.htmlbootstrap

{% for item in page_range %}  不該該寫死，其餘同上
                {% if current_page_num == item %}
                    <li class="active"><a href="?page={{ item }}">{{ item }}</a></li>
                {% else %}
                    <li><a href="?page={{ item }}">{{ item }}</a></li>
                {% endif %}
            {% endfor %}