• 4.Django模板语言和分页


    继承 extends

     子版只能继承一个父模板

    1.父模板 master.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>{% block title %} {% endblock %}</title>
        <link rel="stylesheet" href="/static/common.css">
        <style>
            .pg-header{
                height: 50px;
                background-color: red;
                color:blue
            }
            {% block css %} {% endblock %}
        </style>
    </head>
    <body>
        <div class="pg-header">小男孩管理</div>
    
        {% block content %} {% endblock %}
    
        <div class="pg-footer"></div>
    
        <script src="/static/jquery-1.12.4.js"></script>
    
        {% block js %} {% endblock %}
    </body>
    </html>

    2.子版继承方法

    {% extends 'master.html' %}     #引用母版
    
    {% block title %}用户管理{% endblock %}
    
    {% block content %}
        <h1>用户管理</h1>
        <ul>
            {% for i in u %}
            <li>{{ i }}</li>
            {% endfor %}
        </ul>
    {% endblock %}
    
    {% block css %}
        <style>
            body{
                background-color: black;
            }
        </style>
    {% endblock %}
    
    {% block js %}
        <script>
    
        </script>
    {% endblock %}

    导入定制的组件 include

     创建tag.html

    在index.html中导入tag.html,可以导入很多个

    {% include 'tag.html' %}

    tag.html

    form>
        <input type="text" name="user"/>
        <input type="submit" value="提交"/>
    </form>

    index.html

    {# 指定继承的模板 #}
    {% extends 'master.html' %}
     
    {# 指定替换的位置 #}
    {% block title %}
        tp1
    {% endblock %}
     
    {# 指定替换的位置 #}
    {% block content %}
        <p>tp1</p>
     
        {# 导入单独组件 #}
        {% include 'tag.html' %}
    {% endblock %}

    simple_tag and filter

     1.django默认自带方法

    {{ item.event_start|date:"Y-m-d H:i:s"}}    #日期格式进行转换
    {{ bio|truncatewords:"30" }}                  #取字符串前30位
    {{ my_list|first|upper }}                     #第一个字符大写             
    {{ name|lower }}                                #所有字符小写

     2.simple_tag

    第一步: 在app01下面创建templatetags(必须是这个名字)文件夹
    
    第二步:在templatetags下面创建test1.py文件
    
    第三步:模板中   首先在开头要先导入  {%  load test1 %} 
    
    第四步: 模板中使用方法   {%  函数名 参数1  参数2  %}

    test1.py

    from django import template
    from django.utils.safestring import mark_safe
    # 必须是register对象
    register = template.Library()
    
    @register.simple_tag def func(a1,a2): return a1 + a2

    index.py

    {% load test1 %}
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        {{ name }}
        {{ name|lower }}
    
        {% func 2 5 %}
    </body>
    </html>

    3.filter

    test1.py

    from django import template
    from django.utils.safestring import mark_safe
    # 必须是register对象
    register = template.Library()
    
    @register.simple_tag def func(a1,a2): return a1 + a2 @register.filter() def func1(b1,b2): return b1 + b2

    index.py

    {% load test1 %}
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        {{ name }}
        {{ name|lower }}
    
    {#    simpletag#}
        {% func 2 5 %}
    
    {#    filter#}
        {{ 'zhang'|func1:'derek' }}
    
    
    </body>
    </html>

     总结:

    simple:
    
    优点:参数任意
    
    缺点:不能作为if条件
    
    filter
    
    优点:最多两个参数
    
    缺点:可以作为if条件

     分页

     1.简单分页

     涉及xss攻击,需要用到mark_safe方法,使用此方法字符串传输到后端后,已html形式显示,而非字符串

    HTML文件

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .pagination .page{
                display: inline-block;
                padding: 5px;
                background-color: cyan;
                margin: 5px;
            }
            .pagination .page.active{
                background-color: brown;
                color: white;
            }
        </style>
    </head>
    <body>
        <ul>
            {% for item in li %}
                <li>{{ item }}</li>
            {% endfor %}
        </ul>
        <div class="pagination">
            {{ page_str }}
        </div>
    </body>
    </html>
    user_list.html

    views.py

    from django.shortcuts import render,HttpResponse
    from django.core.handlers.wsgi import WSGIRequest
    from django.utils.safestring import mark_safe
    
    LIST = []
    for i in range(109):
        LIST.append(i)
    
    from django.utils.safestring import  mark_safe
    def user_list(request):
        current_page = request.GET.get('p',1)
        current_page = int(current_page)
    
        start = (current_page-1)*10
        end = current_page*10
        data = LIST[start:end]
    
        all_count = len(LIST)
        count,y = divmod(all_count,10)
        if y :
            count +=1
    
        page_list = []
        for i in range(1,count+1):
            if i == current_page:
                temp = '<a class="page active" href="/user_list/?p=%s">%s</a>'%(i,i)
            else:
                temp = '<a class="page" href="/user_list/?p=%s">%s</a>'%(i,i)
    
            page_list.append(temp)
    
        page_str = mark_safe(''.join(page_list))
    
        return render(request,'user_list.html',{'li':data,'page_str':page_str})

    浏览器访问地址

    浏览器访问地址:http://127.0.0.1:8000/user_list/?p=3

    2.增加功能

    分页数进行定制,添加上一页、下一页,增加跳转功能,实现分页的完整功能

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .pagination .page{
                display: inline-block;
                padding: 5px;
                background-color: cyan;
                margin: 5px;
            }
            .pagination .page.active{
                background-color: brown;
                color: white;
            }
        </style>
    </head>
    <body>
        <ul>
            {% for item in li %}
                <li>{{ item }}</li>
            {% endfor %}
        </ul>
        <div class="pagination">
            {{ page_str }}
        </div>
    </body>
    </html>
    
    user_list.html
    user_list

    views.py

    LIST = []
    for i in range(199):
        LIST.append(i)
    
    from django.utils.safestring import  mark_safe
    def user_list(request):
        current_page = request.GET.get('p',1)
        current_page = int(current_page)
    
        start = (current_page-1)*10
        end = current_page*10
        data = LIST[start:end]
    
        all_count = len(LIST)
        total_count,y = divmod(all_count,10)
        if y :
            total_count +=1
        pager_num = 11                          #页码数
    
        page_list = []
        if total_count < pager_num :            #总页面小于页码数
            start_index = 1
            end_index = total_count + 1
        else:
            if current_page <= pager_num/2:     #开头
                start_index = 1
                end_index = pager_num + 1
            elif current_page + (pager_num-1)/2 >= total_count:         #中间
                start_index = total_count - (pager_num-1)
                end_index = total_count + 1
            else:                               #结尾
                start_index = current_page - (pager_num-1)/2
                end_index = current_page + (pager_num-1)/2 + 1
    
        # 上下页码
        if current_page == 1:
            prev = '<a class="page" href="javascript:void(0)">上一页</a>'  # 什么都不干
        else:
            prev =  '<a class="page" href="/user_list/?p=%s">上一页</a>'%(current_page-1)
        page_list.append(prev)
        for i in range(int(start_index),int(end_index)):
            if i == current_page:
                temp = '<a class="page active" href="/user_list/?p=%s">%s</a>'%(i,i)
            else:
                temp = '<a class="page" href="/user_list/?p=%s">%s</a>'%(i,i)
    
            page_list.append(temp)
        if current_page == total_count:
            nex = '<a class="page" href="javascript:void(0)">下一页</a>'  # 什么都不干
        else:
            nex = '<a class="page" href="/user_list/?p=%s">下一页</a>'%(current_page+1)
        page_list.append(nex)
    
        # 跳转 可以写到前端
        jump = '''
        <input type="text" /><a onclick="jumpTo(this,'/user_list/?p=');">GO</a>
        <script>
            function jumpTo(ths,base) {
                var val = ths.previousSibling.value;
                location.href = base + val;
            }
        </script>
        '''
        page_list.append(jump)
    
        page_str = mark_safe(''.join(page_list))
    
        return render(request,'user_list.html',{'li':data,'page_str':page_str})
    
    

    3.优化完善

    页码代码跟业务代码分开,创建class类,然后views导入进去

    app01下面创建 utils文件夹,里面创建pagination.py

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .pagination .page{
                display: inline-block;
                padding: 5px;
                background-color: cyan;
                margin: 5px;
            }
            .pagination .page.active{
                background-color: brown;
                color: white;
            }
        </style>
    </head>
    <body>
        <ul>
            {% for item in li %}
                <li>{{ item }}</li>
            {% endfor %}
        </ul>
        <div class="pagination">
            {{ page_str }}
        </div>
    </body>
    </html>
    
    user_list.html
    user_list.html

    views.py

    LIST = []
    for i in range(199):
        LIST.append(i)
    
    class Page:
        def __init__(self, current_page, data_count, per_page_count=10, pager_num=7):
            self.current_page = current_page
            self.data_count = data_count
            self.per_page_count = per_page_count
            self.pager_num = pager_num
    
        @property
        def start(self):
            return (self.current_page - 1) * self.per_page_count
    
        @property
        def end(self):
            return self.current_page * self.per_page_count
    
        @property
        def total_count(self):
            v, y = divmod(self.data_count, self.per_page_count)
            if y:
                v += 1
            return v
    
        def page_str(self, base_url):
            page_list = []
    
            if self.total_count < self.pager_num:
                start_index = 1
                end_index = self.total_count + 1
            else:
                if self.current_page <= (self.pager_num + 1) / 2:
                    start_index = 1
                    end_index = self.pager_num + 1
                else:
                    start_index = self.current_page - (self.pager_num - 1) / 2
                    end_index = self.current_page + (self.pager_num + 1) / 2
                    if (self.current_page + (self.pager_num - 1) / 2) > self.total_count:
                        end_index = self.total_count + 1
                        start_index = self.total_count - self.pager_num + 1
    
            if self.current_page == 1:
                prev = '<a class="page" href="javascript:void(0);">上一页</a>'
            else:
                prev = '<a class="page" href="%s?p=%s">上一页</a>' % (base_url, self.current_page - 1,)
            page_list.append(prev)
    
            for i in range(int(start_index), int(end_index)):
                if i == self.current_page:
                    temp = '<a class="page active" href="%s?p=%s">%s</a>' % (base_url, i, i)
                else:
                    temp = '<a class="page" href="%s?p=%s">%s</a>' % (base_url, i, i)
                page_list.append(temp)
    
            if self.current_page == self.total_count:
                nex = '<a class="page" href="javascript:void(0);">下一页</a>'
            else:
                nex = '<a class="page" href="%s?p=%s">下一页</a>' % (base_url, self.current_page + 1,)
            page_list.append(nex)
    
            jump = """
            <input type='text'  /><a onclick='jumpTo(this, "%s?p=");'>GO</a>
            <script>
                function jumpTo(ths,base){
                    var val = ths.previousSibling.value;
                    location.href = base + val;
                }
            </script>
            """ % (base_url,)
    
            page_list.append(jump)
    
            page_str = mark_safe("".join(page_list))
    
            return page_str
    
    from django.utils.safestring import  mark_safe
    def user_list(request):
        current_page = request.GET.get('p', 1)
        current_page = int(current_page)
        page_obj = Page(current_page,len(LIST))
    
        data = LIST[page_obj.start:page_obj.end]
    
        page_str = page_obj.page_str("/user_list/")
    
        return render(request, 'user_list.html', {'li': data,'page_str': page_str})
    
    
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  • 原文地址:https://www.cnblogs.com/derek1184405959/p/8421195.html
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