自定义分页 Cookie Session和获得路径

自定义分页

稳抓稳打版

def publisher_list(request):
    # 从URL中取当前访问的页码数
    try:
        current_page = int(request.GET.get('page'))
    except Exception as e:
        # 取不到或者页码数不是数字都默认展示第1页
        current_page = 1
    # 总数据量
    total_count = models.Publisher.objects.count()
    # 定义每页显示多少条数据
    per_page = 10
    # 计算出总页码数
    total_page, more = divmod(total_count, per_page)
    if more:
        total_page += 1
    # 定义页面上最多显示多少页码(为了左右对称，一般设为奇数)
    max_show = 11
    half_show = max_show // 2
    # 计算一下页面显示的页码范围
    if total_page <= max_show:  # 总页码数小于最大显示页码数
        page_start = 1
        page_end = total_page
    elif current_page + half_show >= total_page:  # 右边越界
        page_end = total_page
        page_start = total_page - max_show
    elif current_page - half_show <= 1:  # 左边越界
        page_start = 1
        page_end = max_show
    else:  # 正常页码区间
        page_start = current_page - half_show
        page_end = current_page + half_show
    # 数据索引起始位置
    data_start = (current_page-1) * per_page
    data_end = current_page * per_page

    publisher_list = models.Publisher.objects.all()[data_start:data_end]

    # 生成页面上显示的页码
    page_html_list = []
    page_html_list.append('<nav aria-label="Page navigation"><ul class="pagination">')
    # 加首页
    first_li = '<li><a href="/publisher_list/?page=1">首页</a></li>'
    page_html_list.append(first_li)
    # 加上一页
    if current_page == 1:
        prev_li = '<li><a href="#"><span aria-hidden="true">&laquo;</span></a></li>'
    else:
        prev_li = '<li><a href="/publisher_list/?page={}"><span aria-hidden="true">&laquo;</span></a></li>'.format(current_page - 1)
    page_html_list.append(prev_li)
    for i in range(page_start, page_end + 1):
        if i == current_page:
            li_tag = '<li class="active"><a href="/publisher_list/?page={0}">{0}</a></li>'.format(i)
        else:
            li_tag = '<li><a href="/publisher_list/?page={0}">{0}</a></li>'.format(i)
        page_html_list.append(li_tag)
    # 加下一页
    if current_page == total_page:
        next_li = '<li><a href="#"><span aria-hidden="true">&raquo;</span></a></li>'
    else:
        next_li = '<li><a href="/publisher_list/?page={}"><span aria-hidden="true">&raquo;</span></a></li>'.format(current_page + 1)
    page_html_list.append(next_li)
    # 加尾页
    page_end_li = '<li><a href="/publisher_list/?page={}">尾页</a></li>'.format(total_page)
    page_html_list.append(page_end_li)
    page_html_list.append('</ul></nav>')
    page_html = "".join(page_html_list)
    return render(request, "publisher_list.html", {"publisher_list": publisher_list, "page_html": page_html})

封装保存版

class Pagination(object):
    """自定义分页（Bootstrap版）"""
    def __init__(self, current_page, total_count, base_url, per_page=10, max_show=11):
        """
        :param current_page: 当前请求的页码
        :param total_count: 总数据量
        :param base_url: 请求的URL
        :param per_page: 每页显示的数据量，默认值为10
        :param max_show: 页面上最多显示多少个页码，默认值为11
        """
        try:
            self.current_page = int(current_page)
        except Exception as e:
            # 取不到或者页码数不是数字都默认展示第1页
            self.current_page = 1
        # 定义每页显示多少条数据
        self.per_page = per_page
        # 计算出总页码数
        total_page, more = divmod(total_count, per_page)
        if more:
            total_page += 1
        self.total_page = total_page
        # 定义页面上最多显示多少页码(为了左右对称，一般设为奇数)
        self.max_show = max_show
        self.half_show = max_show // 2
        self.base_url = base_url

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

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

    def page_html(self):
        # 计算一下页面显示的页码范围
        if self.total_page <= self.max_show:  # 总页码数小于最大显示页码数
            page_start = 1
            page_end = self.total_page
        elif self.current_page + self.half_show >= self.total_page:  # 右边越界
            page_end = self.total_page
            page_start = self.total_page - self.max_show
        elif self.current_page - self.half_show <= 1:  # 左边越界
            page_start = 1
            page_end = self.max_show
        else:  # 正常页码区间
            page_start = self.current_page - self.half_show
            page_end = self.current_page + self.half_show
        # 生成页面上显示的页码
        page_html_list = []
        page_html_list.append('<nav aria-label="Page navigation"><ul class="pagination">')
        # 加首页
        first_li = '<li><a href="{}?page=1">首页</a></li>'.format(self.base_url)
        page_html_list.append(first_li)
        # 加上一页
        if self.current_page == 1:
            prev_li = '<li><a href="#"><span aria-hidden="true">&laquo;</span></a></li>'
        else:
            prev_li = '<li><a href="{}?page={}"><span aria-hidden="true">&laquo;</span></a></li>'.format(
                self.base_url, self.current_page - 1)
        page_html_list.append(prev_li)
        for i in range(page_start, page_end + 1):
            if i == self.current_page:
                li_tag = '<li class="active"><a href="{0}?page={1}">{1}</a></li>'.format(self.base_url, i)
            else:
                li_tag = '<li><a href="{0}?page={1}">{1}</a></li>'.format(self.base_url, i)
            page_html_list.append(li_tag)
        # 加下一页
        if self.current_page == self.total_page:
            next_li = '<li><a href="#"><span aria-hidden="true">&raquo;</span></a></li>'
        else:
            next_li = '<li><a href="{}?page={}"><span aria-hidden="true">&raquo;</span></a></li>'.format(
                self.base_url, self.current_page + 1)
        page_html_list.append(next_li)
        # 加尾页
        page_end_li = '<li><a href="{}?page={}">尾页</a></li>'.format(self.base_url, self.total_page)
        page_html_list.append(page_end_li)
        page_html_list.append('</ul></nav>')
        return "".join(page_html_list)

封装保存版

封装保存版使用示例

def publisher_list(request):
    # 从URL中取当前访问的页码数
    current_page = int(request.GET.get('page'))
    # 比len(models.Publisher.objects.all())更高效
    total_count = models.Publisher.objects.count()
    page_obj = Pagination(current_page, total_count, request.path_info)
    data = models.Publisher.objects.all()[page_obj.start:page_obj.end]
    page_html = page_obj.page_html()
    return render(request, "publisher_list.html", {"publisher_list": data, "page_html": page_html})

 

CBV中加装饰器相关

CBV实现的登录视图

class LoginView(View):

    def get(self, request):
        """
        处理GET请求
        """
        return render(request, 'login.html')

    def post(self, request):
        """
        处理POST请求 
        """
        user = request.POST.get('user')
        pwd = request.POST.get('pwd')
        if user == 'alex' and pwd == "alex1234":
            next_url = request.GET.get("next")
            # 生成随机字符串
            # 写浏览器cookie -> session_id: 随机字符串
            # 写到服务端session：
            # {
            #     "随机字符串": {'user':'alex'}
            # }
            request.session['user'] = user
            if next_url:
                return redirect(next_url)
            else:
                return redirect('/index/')
        return render(request, 'login.html')

要在CBV视图中使用我们上面的check_login装饰器，有以下三种方式：

from django.utils.decorators import method_decorator

1. 加在CBV视图的get或post方法上

from django.utils.decorators import method_decorator


class HomeView(View):

    def dispatch(self, request, *args, **kwargs):
        return super(HomeView, self).dispatch(request, *args, **kwargs)

    def get(self, request):
        return render(request, "home.html")
    
    @method_decorator(check_login)
    def post(self, request):
        print("Home View POST method...")
        return redirect("/index/")

2. 加在dispatch方法上

from django.utils.decorators import method_decorator


class HomeView(View):

    @method_decorator(check_login)
    def dispatch(self, request, *args, **kwargs):
        return super(HomeView, self).dispatch(request, *args, **kwargs)

    def get(self, request):
        return render(request, "home.html")

    def post(self, request):
        print("Home View POST method...")
        return redirect("/index/")

因为CBV中首先执行的就是dispatch方法，所以这么写相当于给get和post方法都加上了登录校验。

3. 直接加在视图类上，但method_decorator必须传 name 关键字参数

如果get方法和post方法都需要登录校验的话就写两个装饰器。

from django.utils.decorators import method_decorator

@method_decorator(check_login, name="get")
@method_decorator(check_login, name="post")
class HomeView(View):

    def dispatch(self, request, *args, **kwargs):
        return super(HomeView, self).dispatch(request, *args, **kwargs)

    def get(self, request):
        return render(request, "home.html")

    def post(self, request):
        print("Home View POST method...")
        return redirect("/index/")

补充

CSRF Token相关装饰器在CBV只能加到dispatch方法上，或者加在视图类上然后name参数指定为dispatch方法。

备注：

　　1.csrf_protect，为当前函数强制设置防跨站请求伪造功能，即便settings中没有设置全局中间件。

　　2.csrf_exempt，取消当前函数防跨站请求伪造功能，即便settings中设置了全局中间件。

from django.views.decorators.csrf import csrf_exempt, csrf_protect
from django.utils.decorators import method_decorator


class HomeView(View):

    @method_decorator(csrf_exempt)
    def dispatch(self, request, *args, **kwargs):
        return super(HomeView, self).dispatch(request, *args, **kwargs)

    def get(self, request):
        return render(request, "home.html")

    def post(self, request):
        print("Home View POST method...")
        return redirect("/index/")

或者

from django.views.decorators.csrf import csrf_exempt, csrf_protect
from django.utils.decorators import method_decorator


@method_decorator(csrf_exempt, name='dispatch')
class HomeView(View):
   
    def dispatch(self, request, *args, **kwargs):
        return super(HomeView, self).dispatch(request, *args, **kwargs)

    def get(self, request):
        return render(request, "home.html")

    def post(self, request):
        print("Home View POST method...")
        return redirect("/index/")

Cookie  和 Session

小知识

    #request.get_full_path()  # 获取当前请求的全路径
    #request.path_info  # 获取当前请求的路径

 

Cookie,Session-----点击这里

2020-04-03