Django之组合查询
一 .Django组合查询
很多电商网站中有组合搜索的功能,所谓组合搜索就是网页中组合多个条件,对数据库中进行查询,并且将结果显示在页面中,下面是所做组合查询效果图：
实现代码如下:
<1>设计数据库
from django.db import models class Direction(models.Model): """ 方向：大数据，人工智能，web开发，系统运维，移动开发 """ name = models.CharField(verbose_name='名称', max_length=32) classification = models.ManyToManyField('Classification') class Meta: db_table = 'Direction' verbose_name_plural = '方向（视频方向）' def __str__(self): return self.name class Classification(models.Model): """ 分类：Python PHP....... """ name = models.CharField(verbose_name='名称', max_length=32) class Meta: db_table = 'Classification' verbose_name_plural = '分类（视频分类）' def __str__(self): return self.name class Level(models.Model): title = models.CharField(max_length=32) class Meta: verbose_name_plural = '难度级别' def __str__(self): return self.title class Video(models.Model): status_choice = ( (1, '下线'), (2, '上线'), ) status = models.IntegerField(verbose_name='状态', choices=status_choice, default=1) level = models.ForeignKey(Level,on_delete=models.CASCADE) classification = models.ForeignKey('Classification', null=True, blank=True,on_delete=models.CASCADE) weight = models.IntegerField(verbose_name='权重（按从大到小排列）', default=0) title = models.CharField(verbose_name='标题', max_length=32) summary = models.CharField(verbose_name='简介', max_length=32) # img = models.ImageField(verbose_name='图片', upload_to='./static/images/Video/') img = models.CharField(verbose_name='图片',max_length=32) href = models.CharField(verbose_name='视频地址', max_length=256) create_date = models.DateTimeField(auto_now_add=True) class Meta: db_table = 'Video' verbose_name_plural = '视频' def __str__(self): return self.title
<2>配置url
from django.conf.urls import url from django.contrib import admin from app01 import views urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^video2-(?P<direction_id>(\d+))-(?P<classification_id>(\d+))-(?P<level_id>(\d+)).html$', views.video2), ]
<3>视图处理部分view.py
from django.shortcuts import render from app01 import models def video2(request,*args,**kwargs): condition = {}#video查询字典 for k, v in kwargs.items(): temp = int(v) kwargs[k] = temp print('kwargs:',kwargs) # (?P<direction_id>(\d+))-(?P<classification_id>(\d+))-(?P<level_id>(\d+)) # 构造查询字典 direction_id = kwargs.get('direction_id') classification_id = kwargs.get('classification_id') level_id = kwargs.get('level_id') direction_list = models.Direction.objects.all() if direction_id == 0:#代表全部方向 class_list = models.Classification.objects.all() if classification_id == 0:#代表全部课程分类 pass else: condition['classification_id'] = classification_id else: direction_obj = models.Direction.objects.filter(id=direction_id).first() class_list = direction_obj.classification.all()#跨表查询所选方向下的所有课程分类 print('class_list:',class_list) class_list_id = direction_obj.classification.all().values_list('id') if not class_list_id: classification_id_list = [] else: classification_id_list = list(zip(*class_list_id))[0] if classification_id == 0: condition['classification_id__in'] = classification_id_list else: if classification_id in classification_id_list:#某课程分类在指定方向课程分类列表中 condition['classification_id'] = classification_id else: # 某课程分类不在指定方向课程分类列表中 kwargs['classification_id'] = 0 condition['classification_id__in'] = classification_id_list if level_id == 0: pass else: condition['level_id'] = level_id print('condition:',condition) level_list = models.Level.objects.all() video_list = models.Video.objects.filter(**condition) return render( request, 'video2.html', { 'kwargs':kwargs, 'direction_list':direction_list, 'class_list':class_list, 'level_list':level_list, 'video_list':video_list } )
<4>页面显示部分
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <style> .condition a{ display: inline-block; padding: 5px 8px; border: 1px solid #dddddd; text-decoration: none; } .condition a.active{ background-color: coral; color: white; text-decoration: none; } </style> </head> <body> <div class="condition"> <h1>筛选</h1> <div> {% if kwargs.direction_id == 0 %} <a class="active" href="/video2-0-{{ kwargs.classification_id }}-{{kwargs.level_id}}.html">全部</a> {% else %} <a href="/video2-0-{{ kwargs.classification_id }}-{{kwargs.level_id}}.html">全部</a> {% endif %} {% for item in direction_list %} {% if item.id == kwargs.direction_id %} <a class="active" href="/video2-{{ item.id }}-{{ kwargs.classification_id }}-{{kwargs.level_id}}.html">{{ item.name }}</a> {% else %} <a href="/video2-{{ item.id }}-{{ kwargs.classification_id }}-{{kwargs.level_id}}.html">{{ item.name }}</a> {% endif %} {% endfor %} </div> <div> {% if kwargs.classification_id == 0 %} <a class="active" href="/video2-{{ kwargs.direction_id}}-0-{{kwargs.level_id}}.html">全部</a> {% else %} <a href="/video2-{{ kwargs.direction_id}}-0-{{kwargs.level_id}}.html">全部</a> {% endif %} {% for item in class_list %} {% if item.id == kwargs.classification_id %} <a class="active" href="/video2-{{ kwargs.direction_id }}-{{ item.id }}-{{kwargs.level_id }}.html">{{ item.name }}</a> {% else %} <a href="/video2-{{ kwargs.direction_id }}-{{ item.id }}-{{kwargs.level_id }}.html">{{ item.name }}</a> {% endif %} {% endfor %} </div> <div> {% if kwargs.level_id == 0 %} <a class="active" href="/video2-{{ kwargs.direction_id}}-{{ kwargs.classification_id }}-0.html">全部</a> {% else %} <a href="/video2-{{ kwargs.direction_id}}-{{ kwargs.classification_id }}-0.html">全部</a> {% endif %} {% for item in level_list %} {% if item.id == kwargs.level_id %} <a class="active" href="/video2-{{ kwargs.direction_id }}-{{ kwargs.classification_id }}-{{ item.id }}.html">{{ item.title }}</a> {% else %} <a href="/video2-{{ kwargs.direction_id }}-{{ kwargs.classification_id }}-{{ item.id }}.html">{{ item.title }}</a> {% endif %} {% endfor %} </div> </div> <div> <h1>结果</h1> {% for row in video_list %} <div>{{ row.title }}</div> <img src="{{ row.img }}"> {% endfor %} </div> </body> </html>
>>>>>>>待续
