Django入门 ----分页功能

• Django自带 Paginator 类来实现分页功能

1. 函数视图使用分页

• page_obj: 分页后的对象列表，在模板中使用for循环遍历即可
• is_paginated: 可选参数。当总页数不超过1页，值为False，此时模板不显示任何分页链接

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

def article_list(request):
    queryset = Article.objects.filter(status='p').order_by('-pub_date')
    paginator = Paginator(queryset, 10)  # 实例化一个分页对象, 每页显示10个
    page = request.GET.get('page')  # 从URL通过get页码，如?page=3
    
    try:
        page_obj = paginator.page(page)
    except PageNotAnInteger:
        page_obj = paginator.page(1) # 如果传入page参数不是整数，默认第一页
    except EmptyPage:
        page_obj = paginator.page(paginator.num_pages)
    
    is_paginated = True if paginator.num_pages > 1 else False # 如果页数小于1不使用分页
    context = {
     'page_obj': page_obj, 'is_paginated': is_paginated}
    return render(request, 'blog/article_list.html', context)

2. 类视图使用分页

• 基于类的视图ListView中使用分页，只需设置paginate_by这个参数即可
• 它同样会向模板传递 page_obj 和 is_paginated 这2个参数

from django.views.generic import ListView
from .models import Article

class ArticleListView(ListView):
    queryset = Article.objects.filter(status='p').order_by('-pub_date')
    template_name = "blog/article_list.html"
    paginate_by = 10 # 每页10条

3. 展示分页的通用模板

• 基本展示

 <ul> 
{
     % for article in page_obj %} 
   <li>{
     {
      article.title }}</li> 
{
     % endfor %}
</ul>

{
     % if is_paginated %}
<div class="pagination">
    <span class="step-links">
        {
     % if page_obj.has_previous %}
            <a href="?page=1">&laquo; first</a>
            <a href="?page={
     { page_obj.previous_page_number }}">上一页</a>
        {
     % endif %}

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

        {
     % if page_obj.has_next %}
            <a href="?page={
     { page_obj.next_page_number }}">下一页</a>
            <a href="?page={
     { page_obj.paginator.num_pages }}">last &raquo;</a>
        {
     % endif %}
    </span>
</div>
{
     % endif %}

• 美化展示

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
 
{
     % if page_obj %}
    <ul> 
    {
     % for article in page_obj %}
       <li> {
     {
      article.title }</li>
     {
     % endfor %}
   </ul>

   {
     # 分页链接 #}
   {
     % if is_paginated %}
     <ul class="pagination">
    {
     % if page_obj.has_previous %}
      <li class="page-item"><a class="page-link" href="?page={
     { page_obj.previous_page_number }}">Previous</a></li>
    {
     % else %}
      <li class="page-item disabled"><span class="page-link">Previous</span></li>
    {
     % endif %}
 
    {
     % for i in page_obj.paginator.page_range %}
        {
     % if page_obj.number == i %}
      <li class="page-item active"><span class="page-link"> {
     {
      i }} <span class="sr-only">(current)</span></span></li>
       {
     % else %}
        <li class="page-item"><a class="page-link" href="?page={
     { i }}">{
     {
      i }}</a></li>
       {
     % endif %}
    {
     % endfor %}
 
      {
     % if page_obj.has_next %}
      <li class="page-item"><a class="page-link" href="?page={
     { page_obj.next_page_number }}">Next</a></li>
    {
     % else %}
      <li class="page-item disabled"><span class="page-link">Next</span></li>
    {
     % endif %}
    </ul>
    {
     % endif %}
 
{
     % else %}
{
     # 注释: 这里可以写自己的句子 #}
{
     % endif %}