• Django【进阶】分页功能Pagination


    项目中,我们需要很多非业务逻辑的功能,例如分页功能,而且此类功能移植性很好,可以在不同的项目中使用,所以整理好这些功能会一定程度上提高开发效率,下面是分页功能代码,使用时,可单独放在utils目录
    """
    使用方法:
    
    from utils.page import Pagination
    def users(request):
        current_page = int(request.GET.get('page',1))
    
        total_item_count = models.UserInfo.objects.all().count()
        # page_obj = Pagination(current_page,total_item_count,request.path_info)  
        # request.path_info,当前请求的页面,也可以直接把请求页面写上,如下
        page_obj = Pagination(current_page,total_item_count,'/users.html')
    
        user_list = models.UserInfo.objects.all()[page_obj.start:page_obj.end]
    
        return render(request,'users.html',{'user_list':user_list,'page_html':page_obj.page_html()})
    
    
    """
    
    
    from django.utils.safestring import mark_safe
    
    class Pagination(object):
    
        def __init__(self,current_page,total_item_count,base_url,per_page_count=10,show_pager_count=11):
            """
            :param current_page:  当前页
            :param total_item_count: 数据库数据总条数
            :param base_url: 分页前缀URL
            :param per_page_count:   每页显示数据条数
            :param show_pager_count: 对多显示的页码
            """
            self.current_page = current_page
            self.total_item_count = total_item_count
            self.base_url = base_url
            self.per_page_count = per_page_count
            self.show_pager_count = show_pager_count
    
            max_pager_num, b = divmod(total_item_count, per_page_count)
            if b:
                max_pager_num += 1
            self.max_pager_num = max_pager_num
    
        @property
        def start(self):
            """
    
            :return:
            """
            return (self.current_page-1)* self.per_page_count
    
        @property
        def end(self):
            """
    
            :return:
            """
            return self.current_page * self.per_page_count
    
        def page_html(self):
            """
    
            :return:
            """
            page_list = []
    
            if self.current_page == 1:
                prev = ' <li><a href="#">上一页</a></li>'
            else:
                prev = ' <li><a href="%s?page=%s">上一页</a></li>' % (self.base_url,self.current_page - 1,)
            page_list.append(prev)
    
            half_show_pager_count = int(self.show_pager_count / 2)
    
            # 数据特别少,15条数据=2页
            if self.max_pager_num < self.show_pager_count:
                # 页码小于11
                pager_start = 1
                pager_end = self.max_pager_num + 1
            else:
                if self.current_page <= half_show_pager_count:
                    pager_start = 1
                    pager_end = self.show_pager_count + 1
                else:
                    if self.current_page + half_show_pager_count > self.max_pager_num:
                        pager_start = self.max_pager_num - self.show_pager_count + 1
                        pager_end = self.max_pager_num + 1
                    else:
                        pager_start = self.current_page - half_show_pager_count
                        pager_end = self.current_page + half_show_pager_count + 1
    
            for i in range(pager_start, pager_end):
                if i == self.current_page:
                    tpl = ' <li class="active"><a href="%s?page=%s">%s</a></li>' % (self.base_url,i, i,)
                else:
                    tpl = ' <li><a href="%s?page=%s">%s</a></li>' % (self.base_url,i, i,)
                page_list.append(tpl)
    
            if self.current_page == self.max_pager_num:
                nex = ' <li><a href="#">下一页</a></li>'
            else:
                nex = ' <li><a href="%s?page=%s">下一页</a></li>' % (self.base_url,self.current_page + 1,)
            page_list.append(nex)
    
            return mark_safe(''.join(page_list)
    

      

     
     
    应用:
     
    创建300条数据
     
    页面显示
     
    用get请求发送页码(get请求,直接在url后面加上"?page=n"就好了)
     
    调用上面的页码类,写好视图函数
     
    前端页面很简单就能显示出来页码
     

     
    思路:
    显示所有——按页显示(每页的起始结束项)——显示页码——当前页样式——上页下页——显示十个页码(当前页前后各五个)——页码前后极限处理

     
  • 相关阅读:
    CSharpGL(26)在opengl中实现控件布局/渲染文字
    CSharpGL(25)一个用raycast实现体渲染VolumeRender的例子
    some OpenGL constants
    CSharpGL(24)用ComputeShader实现一个简单的图像边缘检测功能
    CSharpGL(23)用ComputeShader实现一个简单的ParticleSimulator
    CSharpGL(22)实现顺序无关的半透明渲染(Order-Independent-Transparency)
    CSharpGL(21)用鼠标拾取、拖拽VBO图元内的点、线或本身
    批量重命名文件
    [译]基于GPU的体渲染高级技术之raycasting算法
    CSharpGL(20)用unProject和Project实现鼠标拖拽图元
  • 原文地址:https://www.cnblogs.com/lucaq/p/7587464.html
Copyright © 2020-2023  润新知