Django-自定義分頁

封裝好的自定義分頁器

class Page():

    def __init__(self, page_num, total_count, base_url, params, per_page=10, max_page=11):

        """
        page_num: 當前頁碼數
        total_count: 數據總數
        base_url: a標籤href的前綴
        params: request對象，是QueryDict類型
        per_page: 每頁顯示多少條數據
        max_page: 單一頁面上最多顯示幾個頁碼
        """

        self.page_num = page_num
        self.total_count = total_count
        self.base_url = base_url
        self.params = params
        self.per_page = per_page
        self.max_page = max_page

        # 總頁碼
        total_page, m = divmod(self.total_count, self.per_page)

        if m:
            total_page += 1
        self.total_page = total_page

        try:
            self.page_num = int(self.page_num)
            # print("self.page_num==>", self.page_num) 1
            # 如果輸入的頁碼數大於最大的頁碼數，默認返回第一頁
            if self.page_num > self.total_page:
                self.page_num = self.total_page
            elif self.page_num <= 0:
                self.page_num = 1
        except Exception as e:
            # 當輸入的頁碼不是數字時，返回第一頁
            self.page_num = 1
        #如果當前頁碼數爲0，那麼數據開始位置也是0
        if self.page_num == 0:
            self.data_start = self.page_num
        # 定義兩個變量保存數據從哪取到哪
        else:
            self.data_start = (self.page_num - 1) * 10

        self.data_end = self.page_num * 10

        #頁面上總共展示多少頁碼
        #如果總頁數小於設定的單頁顯示頁碼數
        if self.total_page < self.max_page:
            self.max_page = self.total_page
        # 讓選定頁碼取中，計算左右兩邊長度
        self.half_max_page = self.max_page // 2

        # 頁面上展示的頁碼從哪開始
        self.page_start = self.page_num - self.half_max_page
        # 頁面上展示的頁碼從哪結束
        self.page_end = self.page_num + self.half_max_page
        # 如果開始頁數小於1
        if self.page_start <= 1:
            self.page_start = 1
            self.page_end = self.max_page
        # 如果結束頁面大於最大頁碼數
        elif self.page_end >= self.total_page:
            self.page_start = self.total_page - self.max_page + 1
            self.page_end = self.total_page

        #拷貝一份request對象，是個QueryDict形式，後面會用於獲取及修改url
        import copy
        self.params = copy.deepcopy(self.params) #{"page":"12","title_startwith":"py","id_gt":"5"}

    @property
    def start(self):
        return self.data_start

    @property
    def end(self):
        return self.data_end

    def page_html(self):

        # 自己拼接分頁的HTML代碼
        html_str_list = []
        print("html_str_list==>", html_str_list)
        # 加上上一頁標籤
        #判斷一下如果是第一頁就沒有上一頁了
        if self.page_num <= 1:
            html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">«</span></a></li>')
        #否則加上上一頁
        else:
            self.params["page"] = self.page_num - 1
            html_str_list.append('<li><a href="{0}?{1}"><span aria-hidden="true">«</span></a></li>'.format(self.base_url ,self.params.urlencode()))

        # 加上首頁
        self.params["page"] = 1
        html_str_list.append('<li><a href="{0}?{1}">首頁</a></li>'.format(self.base_url, self.params.urlencode()))

        for i in range(self.page_start, self.page_end + 1):
            #把QueryDict中的page修改爲當前循環的頁碼
            self.params["page"] = i
            # 如果i等於當前頁就加一個樣式類
            if i == self.page_num:
                tmp = '<li class="active"><a href="{0}?page={1}">{2}</a></li>'.format(self.base_url, self.params.urlencode(), i)
            else:
                tmp = '<li><a href="{0}?{1}">{2}</a></li>'.format(self.base_url, self.params.urlencode(), i)
            html_str_list.append(tmp)

        # 加上尾頁
        self.params["page"] = self.total_page
        html_str_list.append('<li><a href="{0}?{1}">尾頁</a></li>'.format(self.base_url, self.params.urlencode()))

        # 加上下一頁標籤
        #判斷，如果是最後一頁，就沒有下一頁
        if self.page_num >= self.total_page:
            html_str_list.append('<li class="disabled"><a href="#"><span aria-hidden="true">»</span></a></li>')
        else:
            self.params["page"] = self.page_num + 1
            html_str_list.append('<li><a href="{0}?{1}"><span aria-hidden="true">»</span></a></li>'.format(self.base_url, self.params.urlencode()))

        page_html = "".join(html_str_list)

        return page_html