标签：level https 接收 com foreign inline class datetime lambda
现在很多网站都会有这样的组合搜索功能，其实质是几个模型之间组合对数据库进行查询，并将结果显示到页面上。
每一行都是一个模型，模型之间有着连表关系（一对多、多对多等）
from django.db import models
class Direction(models.Model):
"""方向：自动化、测试、运维、前端"""
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）' # 模型的复数形式，若不指定则在后面加一个 s
def __str__(self):
return self.name
class Classification(models.Model):
"""分类：Python、Linux、JavaScript、OpenStack、Node.js、C"""
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):
"""等级：初级、中级、高级、骨灰级"""
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（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=100)
# 也可以用 ImgField 或 FileField 存储图片，而不是 CharField，但是要指定存储路径
# img = models.ImgField(verbose_name='图片', upload_to='app/static/app/video')
img = models.CharField(verbose_name='图片', max_length=200)
href = models.CharField(verbose_name='视频地址', max_length=256)
create_data = models.DateTimeField(auto_now_add=True)
class Meta:
db_table = 'Video'
verbose_name_plural = '视频'
def __str__(self):
return self.titleurlconf 配置采用的是二级路由，即应用本身创建 urls.py：
# project/urls.py
from django.contrib import admin
from django.urls import path, include
urlpatterns = [
path('admin/', admin.site.urls),
path('app/', include('app.urls')),
]
# app/urls.py
from django.urls import path
from app import views
urlpatterns = [
path('video/<int:classification_id>/<int:level_id>/<int:status>/', views.video, name='video'),
path('video2/<int:direction_id>/<int:classification_id>/<int:level_id>/', views.video2, name='video2'),
]一对多关系中主要是视频信息与分类、等级之间的关系操作。
函数接收三个额外参数，分别为：分类 classification id、等级 level id 以及状态 status id。根据这三个参数构造查询条件（filter() 函数本身是支持字典形式查询的）。
Tips
condition 构造的查询条件是字典形式，其键 key应与数据表中相应字段对应，如： classification_id 为模型 Video与 Classification 的外键字段名。
from django.shortcuts import render, HttpResponse
from app.models import Level, Classification, Direction, Video
def video(request, *args, **kwargs):
print(args, kwargs) # () {'classification_id': 1, 'level_id': 2}
# 构造查询条件
condition = {
# 'classification_id': 0,
# 'level_id': 0
}
# 当 kwargs = {'classification_id': 0, 'level_id': 0} 时，condition = {}，
# Video.objects.filter(**condition) 能把所有的都查出来
# 当 kwargs = {'classification_id': 1, 'level_id': 1} 时，condition = {'classification_id': 1, 'level_id': 1}
# filter() 支持字典格式
# 将其转换为整数
for k, v in kwargs.items():
temp = int(v)
kwargs[k] = temp
if temp:
condition[k] = temp
class_list = Classification.objects.all()
level_list = Level.objects.all()
# 查询数据
video_list = Video.objects.filter(**condition)
"""
status_choice = (
(1, '下线'),
(2, '上线'),
)
"""
# status_list：[{'id': 1, 'name': '下线'}, {'id': 2, 'name': '上线'}]
status_list = list(map(lambda x: {'id': x[0], 'name': x[1]}, Video.status_choice))
return render(
request,
'app/video.html',
{
'kwargs': kwargs,
'class_list': class_list,
'level_list': level_list,
'video_list': video_list,
'status_list': status_list
}
){% load static %}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>视频</title>
<style type="text/css">
.box1 a{
display: inline-block;
padding: 5px 8px;
border: 1px solid #dddddd;
}
.box1 a.active{
background-color: coral;
color: white;
}
</style>
</head>
<body>
<div class="box1">
<h1>筛选</h1>
<!--分类-->
<div>
{% if kwargs.classification_id == 0 %}
<a class="active" href="/app/video/0/{{ kwargs.level_id }}/{{ kwargs.status }}">全部</a>
{% else %}
<a href="/app/video/0/{{ kwargs.level_id }}/{{ kwargs.status }}">全部</a>
{% endif %}
{% for class in class_list %}
{% if class.id == kwargs.classification_id %}
<a href="/app/video/{{ class.id }}/{{ kwargs.level_id }}/{{ kwargs.status }}" class="active">{{ class.name }}</a>
{% else %}
<a href="/app/video/{{ class.id }}/{{ kwargs.level_id }}/{{ kwargs.status }}">{{ class.name }}</a>
{% endif %}
{% endfor %}
</div>
<!--等级-->
<div>
{% if kwargs.level_id == 0 %}
<a href="/app/video/{{ kwargs.classification_id }}/0/{{ kwargs.status }}" class="active">全部</a>
{% else %}
<a href="/app/video/{{ kwargs.classification_id }}/0/{{ kwargs.status }}">全部</a>
{% endif %}
{% for level in level_list %}
{% if level.id == kwargs.level_id %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ level.id }}/{{ kwargs.status }}" class="active">{{ level.title }}</a>
{% else %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ level.id }}/{{ kwargs.status }}">{{ level.title }}</a>
{% endif %}
{% endfor %}
</div>
<!--状态-->
<div>
{% if kwargs.status == 0 %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ kwargs.level_id }}/0" class="active">全部</a>
{% else %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ kwargs.level_id }}/0">全部</a>
{% endif %}
{% for status in status_list %}
{% if status.id == kwargs.status %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ kwargs.level_id }}/{{ status.id }}" class="active">{{ status.name }}</a>
{% else %}
<a href="/app/video/{{ kwargs.classification_id }}/{{ kwargs.level_id }}/{{ status.id }}">{{ status.name }}</a>
{% endif %}
{% endfor %}
</div>
</div>
<div>
<h1>结果</h1>
<div>
{% for video in video_list %}
<p>{{ video.title }}</p>
<img src="{{ video.href }}">
{% endfor %}
</div>
</div>
</body>
</html>
多对多关系中主要是方向与分类之间的关系操作。
from django.shortcuts import render, HttpResponse
from app.models import Level, Classification, Direction, Video
def video2(request, *args, **kwargs):
"""
多对多："方向-分类
方向：自动化、测试、运维、前端
分类：Python、Linux、JavaScript、OpenStack、Node.js、C
等级：初级、中级、高级、骨灰级
"""
print(kwargs) # {'direction_id': 1, 'classification_id': 4, 'level_id': 2}
direction_id = kwargs.get('direction_id')
classification_id = kwargs.get('classification_id')
level_id = kwargs.get('level_id')
condition = {} # 条件 构造查询字典
# 方向：全部列举
direction_list = Direction.objects.all()
# 若方向为 0，则分类显示全部
if direction_id == 0:
# 若分类也为 0，分类显示全部
class_list = Classification.objects.all()
if classification_id == 0:
pass
else:
condition['classification_id'] = classification_id
# 若方向不为 0，则根据方向查询分类
else:
direction_obj = Direction.objects.filter(id=direction_id)[0]
class_list = direction_obj.classification.all() # 根据多对多名字+方向的ID，获取相应分类列表
# < QuerySet[ < Classification: Python >, < Classification: Linux >] >
# 根据方向 id 获取分类的 id 列表
vlist = direction_obj.classification.all().values_list('id') # < QuerySet[(1,), (5,)] >
# 若哪个方向下没有分类
if not vlist:
classification_id_list = []
else:
# 转换为元组
classification_id_list = list(zip(*vlist))[0] # (1, 5)
# 若分类为 0，则显示相应分类
if classification_id == 0:
condition['classification_id__in'] = classification_id_list
else:
if classification_id in classification_id_list:
condition['classification_id'] = classification_id
else:
condition['classification_id__in'] = classification_id_list
if level_id == 0:
pass
else:
condition['level_id'] = level_id
# 等级：全部列举
level_list = Level.objects.all()
video_list = Video.objects.filter(**condition)
return render(
request,
'app/video2.html',
{
'direction_list': direction_list,
'level_list': level_list,
'kwargs': kwargs,
'video_list': video_list,
'class_list': class_list
}
)<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>多对多和一对多</title>
<style type="text/css">
.box1 a {
display: inline-block;
padding: 5px 8px;
border: 1px solid #dddddd;
}
.box1 a.active {
background-color: coral;
color: white;
}
</style>
</head>
<body>
<div class="box1">
<h1>筛选</h1>
<!--方向-->
<div>
{% if kwargs.direction_id == 0 %}
<a class="active" href="{% url 'video2' direction_id=0 classification_id=kwargs.classification_id level_id=kwargs.level_id %}">全部</a>
{% else %}
<a href="{% url 'video2' direction_id=0 classification_id=kwargs.classification_id level_id=kwargs.level_id %}">全部</a>
{% endif %}
{% for direction in direction_list %}
{% if direction.id == kwargs.direction_id %}
<a href="{% url 'video2' direction_id=direction.id classification_id=kwargs.classification_id level_id=kwargs.level_id %}" class="active">{{ direction.name }}</a>
{% else %}
<a href="{% url 'video2' direction_id=direction.id classification_id=kwargs.classification_id level_id=kwargs.level_id %}">{{ direction.name }}</a>
{% endif %}
{% endfor %}
</div>
<!--分类-->
<div>
{% if kwargs.classification_id == 0 %}
<a class="active" href="{% url 'video2' direction_id=kwargs.direction_id classification_id=0 level_id=kwargs.level_id %}">全部</a>
{% else %}
<a href="{% url 'video2' direction_id=kwargs.direction_id classification_id=0 level_id=kwargs.level_id %}">全部</a>
{% endif %}
{% for class in class_list %}
{% if class.id == kwargs.classification_id %}
<a class="active" href="{% url 'video2' direction_id=kwargs.direction_id classification_id=class.id level_id=kwargs.level_id %}">{{ class.name }}</a>
{% else %}
<a href="{% url 'video2' direction_id=kwargs.direction_id classification_id=class.id level_id=kwargs.level_id %}">{{ class.name }}</a>
{% endif %}
{% endfor %}
</div>
<!--等级-->
<div>
{% if kwargs.level_id == 0 %}
<a class="active" href="{% url 'video2' direction_id=kwargs.direction_id classification_id=kwargs.classification_id level_id=0 %}">全部</a>
{% else %}
<a href="{% url 'video2' direction_id=kwargs.direction_id classification_id=kwargs.classification_id level_id=0 %}">全部</a>
{% endif %}
{% for level in level_list %}
{% if level.id == kwargs.level_id %}
<a class="active" href="{% url 'video2' direction_id=kwargs.direction_id classification_id=kwargs.classification_id level_id=level.id %}">{{ level.title }}</a>
{% else %}
<a href="{% url 'video2' direction_id=kwargs.direction_id classification_id=kwargs.classification_id level_id=level.id %}">{{ level.title }}</a>
{% endif %}
{% endfor %}
</div>
</div>
<div>
<h1>结果</h1>
{% for video in video_list %}
<p>{{ video.title }}</p>
{% endfor %}
</div>
</body>
</html>
参考博客
标签：level https 接收 com foreign inline class datetime lambda
原文地址：https://www.cnblogs.com/midworld/p/11380491.html
