python - 分頁代碼

1.　　分頁的基礎 

views.py

 

    # 分頁代碼
    page = int(request.GET.get('page', 1))
    paeg_size = 10
    start = (page - 1) * paeg_size
    end = page * paeg_size

　　# 查詢結果輸出 
    number_lits = models.Number.objects.filter(**data_dict).order_by('-price')[start:end]

 

2.　　html

<nav aria-label="Page navigation">
              <ul class="pagination">
                    <li>
                      <a href="#" aria-label="Previous">
                        <span aria-hidden="true">&laquo;</span>
                      </a>
                    </li>
                    <li><a href="?page=1">1</a></li>
                    <li><a href="?page=2">2</a></li>
                    <li><a href="?page=3">3</a></li>
                    <li><a href="?page=4">4</a></li>
                    <li><a href="?page=5">5</a></li>
                    <li>
                      <a href="#" aria-label="Next">
                        <span aria-hidden="true">&raquo;</span>
                      </a>
                    </li>
              </ul>
</nav>

 

---

 

 

正式分頁代碼 (不完整):

pagetions.py  代碼  

 

'''
自定義分頁組件
views.py 代碼

# 引入模塊
from app.utils.pagetions import Pagetions

queryset = models.Number.objects.filter(**data_dict).order_by('id')

page_object = Pagetions(request, queryset)
    context = {
        'queryset': page_object.page_queryset,
        'page_string': page_object.html()
    }
return render(request, 'number_list.html',context )





在html 頁面中代碼
 {% for item in queryset %}
    {{ item.字段 }}
{% endfor %}
<ul class="pagination">
   {{ page_string }}
</ul>


'''
#page_string = ''.join(page_ste_list) 變為安全必須得導包
from django.utils.safestring import mark_safe

class Pagetions(object):
    def __init__(self, request, queryset, page_param='page', page_size=10, plus=3):
        page = int(request.GET.get(page_param, "1"))
        # if page.isdecimal:
        #     page = int(page)
        # else:
        #     page = 1

        self.page = page
        self.page_size = page_size

        self.start = (page - 1) * page_size  # 開始數據
        self.end = page * page_size  # 結束數據

        self.page_queryset = queryset[self.start: self.end]

        # 查詢數據庫中所有數據的  個數
        total_count = queryset.count()
        # 總頁碼
        total_page_count, div = divmod(total_count, page_size)
        if div:
            total_page_count += 1
        self.total_page_count = total_page_count
        self.plus = plus

    def html(self):
        # 計算頁碼顯示 前后頁數

        # 極致的判斷
        if self.total_page_count <= 2 * self.plus + 1:
            start_page = 1
            end_page = self.total_page_count
        else:

            # 第一頁的極值處理方式 當數據小於 3
            if self.page <= self.plus:
                start_page = 1
                end_page = 2 * self.plus + 1
            else:
                # 最后一頁極值 處理方式
                if self.page + self.plus > self.total_page_count:
                    end_page = self.total_page_count
                    start_page = self.total_page_count - 2 * self.plus
                else:
                    start_page = self.page - self.plus
                    end_page = self.page + self.plus

        # 頁碼
        page_str_list = []

        # 首頁
        page_str_list.append('<li class="hidden-xs"><a href="?page={}"> 首頁 </a></li>'.format(1))
        # 上一頁
        if self.page > 1:
            pev = '<li><a href="?page={}"> 上一頁 </a></li>'.format(self.page - 1)
        else:
            pev = '<li><a href="?page={}"> 上一頁 </a></li>'.format(1)
        page_str_list.append(pev)

        # 中間頁面
        for i in range(start_page, end_page + 1):
            if i == self.page:
                ele = '<li class="active"><a href="?page={}">{}</a></li>'.format(i, i)
            else:
                ele = '<li><a href="?page={}">{}</a></li>'.format(i, i)
            page_str_list.append(ele)

        # 下一頁
        if self.page < self.total_page_count:
            pev = '<li><a href="?page={}"> 下一頁 </a></li>'.format(self.page + 1)
        else:
            pev = '<li><a href="?page={}"> 下一頁 </a></li>'.format(self.total_page_count)
        page_str_list.append(pev)

        # 尾頁
        page_str_list.append('<li class="hidden-xs"><a href="?page={}"> 尾頁 </a></li>'.format(self.total_page_count))

        # 調轉頁面
        search_str =''' 
                <form method="get">
                    <div class="col-sm-3 hidden-xs">
                        <div class="input-group">
                          <input type="text" name="page" class="form-control" placeholder="搜索">
                          <span class="input-group-btn">
                            <button class="btn btn-default" type="submit">跳轉</button>
                          </span>
                        </div>
                    </div>
                </form>
            '''
        page_str_list.append(search_str)
        # mark_safe() 需要導包
        page_string = mark_safe(''.join(page_str_list))
        return page_string