自定義分頁器

自定義分頁器

def change_page(request, all_num, url):
    page_html = []
    max_page = 10 // 最多顯示10頁
    current_page = request.GET.get("page")

    if current_page:
        page = current_page
    else:
        page = 1
    page = int(page)
　　
　　data_num = 10  // 一頁顯示的數據的條數

    all_page, n = divmod(all_num, data_num)
    if all_page > 0:
        if n == 0:
            all_page1 = all_page
        else:
            all_page1 = all_page + 1
    else:
        all_page1 = 1

    ret = page + 1
    res = page - 1

    if ret > all_page1:
        ret = all_page1
    if res < 1:
        res = 1
    if all_page1 < max_page + 1:
        page_start = 1
        page_end = all_page1
    else:
        page_start = page
        page_end = page_start + max_page

    if page_end > all_page1:
        page_end = all_page1
        page_start = page_end - 10

    page_html.append(
        '<li><a href="/{}/?page=1"><span aria-hidden="true">首頁</span></a></li>'.format(url))
    page_html.append(
        '<li><a href="/{}/?page={}"><span aria-hidden="true">&laquo;</span></a></li>'.format(url, res))
    for i in range(page_start, page_end + 1):
        if i == page:
            page_html.append('<li class="active"><a href="/{}/?page={}">{}</a></li>'.format(url, i, i))
        else:
            page_html.append('<li><a href="/{}/?page={}">{}</a></li>'.format(url, i, i))

    page_html.append(
        '<li><a href="/{}/?page={}"><span aria-hidden="true">&raquo;</span></a></li>'.format(url, ret))
    page_html.append(
        '<li><a href="/{}/?page={}"><span aria-hidden="true">尾頁</span></a></li>'.format(url, all_page1))
    page_html = "".join(page_html)

    num_start = (page - 1) * 10
    num_last = page * 10
    return page_html, num_start, num_last

 

 

基於面向對象的分頁器

class Pagination(object):
    def __init__(self,current_page,all_count,per_page_num=2,pager_count=11):
        """
        封裝分頁相關數據
        :param current_page: 當前頁
        :param all_count:    數據庫中的數據總條數
        :param per_page_num: 每頁顯示的數據條數
        :param pager_count:  最多顯示的頁碼個數
        
        用法:
        queryset = model.objects.all()
        page_obj = Pagination(current_page,all_count)
        page_data = queryset[page_obj.start:page_obj.end]
        獲取數據用page_data而再也不使用原始的queryset
        獲取前端分頁樣式用page_obj.page_html
        """
        try:
            current_page = int(current_page)
        except Exception as e:
            current_page = 1

        if current_page <1:
            current_page = 1

        self.current_page = current_page

        self.all_count = all_count
        self.per_page_num = per_page_num


        # 總頁碼
        all_pager, tmp = divmod(all_count, per_page_num)
        if tmp:
            all_pager += 1
        self.all_pager = all_pager

        self.pager_count = pager_count
        self.pager_count_half = int((pager_count - 1) / 2)

    @property
    def start(self):
        return (self.current_page - 1) * self.per_page_num

    @property
    def end(self):
        return self.current_page * self.per_page_num

    def page_html(self):
        # 若是總頁碼 < 11個：
        if self.all_pager <= self.pager_count:
            pager_start = 1
            pager_end = self.all_pager + 1
        # 總頁碼  > 11
        else:
            # 當前頁若是<=頁面上最多顯示11/2個頁碼
            if self.current_page <= self.pager_count_half:
                pager_start = 1
                pager_end = self.pager_count + 1

            # 當前頁大於5
            else:
                # 頁碼翻到最後
                if (self.current_page + self.pager_count_half) > self.all_pager:
                    pager_end = self.all_pager + 1
                    pager_start = self.all_pager - self.pager_count + 1
                else:
                    pager_start = self.current_page - self.pager_count_half
                    pager_end = self.current_page + self.pager_count_half + 1

        page_html_list = []
        # 添加前面的nav和ul標籤
        page_html_list.append('''
                    <nav aria-label='Page navigation>'
                    <ul class='pagination'>
                ''')
        first_page = '<li><a href="?page=%s">首頁</a></li>' % (1)
        page_html_list.append(first_page)

        if self.current_page <= 1:
            prev_page = '<li class="disabled"><a href="#">上一頁</a></li>'
        else:
            prev_page = '<li><a href="?page=%s">上一頁</a></li>' % (self.current_page - 1,)

        page_html_list.append(prev_page)

        for i in range(pager_start, pager_end):
            if i == self.current_page:
                temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i,)
            else:
                temp = '<li><a href="?page=%s">%s</a></li>' % (i, i,)
            page_html_list.append(temp)

        if self.current_page >= self.all_pager:
            next_page = '<li class="disabled"><a href="#">下一頁</a></li>'
        else:
            next_page = '<li><a href="?page=%s">下一頁</a></li>' % (self.current_page + 1,)
        page_html_list.append(next_page)

        last_page = '<li><a href="?page=%s">尾頁</a></li>' % (self.all_pager,)
        page_html_list.append(last_page)
        # 尾部添加標籤
        page_html_list.append('''
                                           </nav>
                                           </ul>
                                       ''')
        return ''.join(page_html_list)