知识点的回顾：

• 安装Django

  pip install django
  

• 创建Django项目

  >>> django-admin startproject mysite
  

  注意：Pycharm可以创建。如果Pycharm创建，记得settings.py中的DIR templates删除。

• 创建app&注册

  >>>python manage.py startapp app01
  >>>python manage.py startapp app02
  >>>python manage.py startapp app03
  

  INSTALLED_APPS = ["django.contrib.admin","django.contrib.auth","django.contrib.contenttypes","django.contrib.sessions","django.contrib.messages","django.contrib.staticfiles","app01.apps.App01Config"
  ]
  

  注意：否则app下的models.py写类时，无法在数据库中创建表。

• 配置静态文件路径&模板的路径（放在app目录下）。

• 配置数据库相关操作（MySQL）

  • 第三方模块（django3版本）

    pip install mysqlclient
    

  • 自己先去MySQL创建一个数据库。

  • 配置数据库连接settings.py

    DATABASES = {'default':{'ENGINE': 'django.db.backends.mysql',  # 数据库引擎'NAME': 'gx_day16',  # 数据库名称'HOST': '127.0.0.1',  # 数据库地址，本机 ip 地址 127.0.0.1'PORT': 3306,  # 端口'USER': 'root',  # 数据库用户名'PASSWORD': 'xxxx',  # 数据库密码}
    }
    

  • 在app下的models.py中编写

    nfrom django.db import modelsclass Admin(models.Model):""" 管理员 """username = models.CharField(max_length=32, verbose_name='用户名')password = models.CharField(max_length=64, verbose_name='密码')def __str__(self):return self.usernameclass Department(models.Model):""" 部门表 """title = models.CharField(max_length=32, verbose_name='标题')def __str__(self):return self.title
    

  • 执行两个命令：

    >>>python manage.py makemigrations
    >>>python manage.py migrate
    

• 在url.py，路由（url和函数的关系）

• 在views.py，视图函数，编写业务逻辑

• templates目录，编写HTML模板（含有模板语法、继承、{% static 'xx'%}）

• ModelForm & Form组件，在我们开发增删改查功能

  • 生成HTML标签（生成默认值）
  • 请求数据进行校验
  • 保存到数据库（ModelForm）
  • 获取错误信息

• Cookie和Session，用户登录信息保存起来

• 中间件，基于中间件实现用户认证，基于：process_request

• ORM操作

  models.User.objects.filter(id="xxx")
  models.User.objects.filter(id="xxx").order_by("-id")
  

• 分页组件

1.Ajax请求

2.订单

表结构

class Order(models.Model):""" 订单 """oid = models.CharField(max_length=64, verbose_name='订单号')title = models.CharField(max_length=32, verbose_name='名称')price = models.IntegerField(verbose_name='价格')status_choice = ((1, '待支付'),(2, '已支付'),)status = models.SmallIntegerField(choices=status_choice, verbose_name='状态', default=1)admin = models.ForeignKey(verbose_name="管理员", to="Admin", on_delete=models.CASCADE)

想要去数据库中获取数据时：对象/字典

# 对象，当前行的所有数据。
row_object = models.Order.objects.filter(id=uid).first()
row_object.id
row_object.title

# 字典，{"id":1,"title":"xx"}
row_dict = models.Order.objects.filter(id=uid).values("id","title").first()

# queryset = [obj,obj,obj]
queryset = models.Order.objects.all()

# queryset = [{"id":1,"title":"xx"},{"id":2,"title":"xx"},]
queryset = models.Order.objects.all().values("id","title")

# queryset = [(1,"xx"),(2,"xx"),]
queryset = models.Order.objects.all().values_list("id","title")

小结

3.图表

• highchart，国外
• echarts，国内

更多参考文档：https://echarts.apache.org/examples/zh/index.html#chart-type-line

4.关于文件上传

4.1基本操作

{% extends 'layout.html' %}{% block content %}<div class="container"><form method="post" enctype="multipart/form-data">{% csrf_token %}<input type="text" name="username"><input type="file" name="avatar"><input type="submit" name="提交"></form></div>
{% endblock %}

# 'username': ['lingze']
print(request.POST)  # 请求体中数据
# {'avatar': [<InMemoryUploadedFile: 1.png (image/png)>]}
print(request.FILES)   # 请求发过来的文件

from django.shortcuts import HttpResponse, renderdef upload_list(request):if request.method == 'GET':return render(request, 'upload_list.html')# 'username': ['lingze']# print(request.POST)  # 请求体中数据# {'avatar': [<InMemoryUploadedFile: 1.png (image/png)>]}# print(request.FILES)   # 请求发过来的文件file_object = request.FILES.get("avatar")print(file_object.name)f = open(file_object.name, mode='wb')for chunk in file_object.chunks():f.write(chunk)f.close()return HttpResponse("....")

案例：批量上传数据

<form method="post" enctype="multipart/form-data" action="/depart/multi/">{% csrf_token %}<div class="form-group"><input type="file" name="exc"></div><input type="submit" value="上传" class="btn btn-info btn-sm">
</form>

def depart_multi(request):""" 批量上传（Excel文件）"""# 1、获取用户上传的文件对象file_object = request.FILES.get('exc')print(type(file_object))# 2、直接打开Excel并读取内容wb = load_workbook(file_object)sheet = wb.worksheets[0]# 3、循环获取每一行数据for row in sheet.iter_rows(min_row=2):text = row[0].valueexists = models.Department.objects.filter(title=text).exists()if not exists:models.Department.objects.create(title=text)return redirect('/depart/list/')

案例：混合数据（Form）

提交页面时：用户输入数据+文件（输入不能为空、报错）。

• Form生成HTML标签：type=file
• 表单的验证
• form.cleaned_data 获取 数据 + 文件对象

{% extends 'layout.html' %}{% block content %}<div class="container"><div class="panel panel-default"><div class="panel-heading"><h3 class="panel-title">{{ title }}</h3></div><div class="panel-body"><form method="post" enctype="multipart/form-data" novalidate>{% csrf_token %}{% for field in form %}<div class="form-group"><label>{{ field.label }}</label>{{ field }}<span style="color: red">{{ field.errors.0 }}</span></div>{% endfor %}<button type="submit" class="btn btn-primary">提 交</button></form></div></div></div>{% endblock %}

from django.shortcuts import HttpResponse, render
from django import forms
from app01.utils.bootstrap import BootStrapForm
import os
from app01 import modelsdef upload_list(request):if request.method == 'GET':return render(request, 'upload_list.html')# 'username': ['lingze']# print(request.POST)  # 请求体中数据# {'avatar': [<InMemoryUploadedFile: 1.png (image/png)>]}# print(request.FILES)   # 请求发过来的文件file_object = request.FILES.get("avatar")print(file_object.name)f = open(file_object.name, mode='wb')for chunk in file_object.chunks():f.write(chunk)f.close()return HttpResponse("....")class UpForm(BootStrapForm):bootstrap_exclude_fields = ['img']name = forms.CharField(label="姓名")age = forms.IntegerField(label="年龄")img = forms.FileField(label="头像")def upload_form(request):title = "Form上传"if request.method == 'GET':form = UpForm()return render(request, 'upload_form.html', {'title': title, 'form': form})form = UpForm(data=request.POST, files=request.FILES)if form.is_valid():# {'name': '吴佩琦2', 'age': 19, 'img': <InMemoryUploadedFile: apple.png (image/png)>}# print(form.cleaned_data)# 1、读取图片内容，写入到文件夹中并获取文件的路径。image_object = form.cleaned_data.get("img")db_file_path = os.path.join("static", "img", image_object.name)file_path = os.path.join("app01", "static", "img", image_object.name)f = open(file_path, 'wb')for chunk in image_object.chunks():f.write(chunk)f.close()# 2、将图片文件路径写入到数据库models.Boss.objects.create(name=form.cleaned_data.get("name"),age=form.cleaned_data.get("age"),img=db_file_path,)return HttpResponse("...")return render(request, 'upload_form.html', {'title': title, 'form': form})

注意：就目前而言，所有的静态文件都只能放在static目录。

在django的开发过程中两个特殊的文件夹：

• static，存放静态文件的路径，包括：CSS、JS、项目图片。
• media，用户上传的数据的目录。

4.2启用media

在urls.py中进行配置：

from django.conf import settings
from django.urls import path, re_path
from django.views.static import servere_path(r'^media/(?P<path>.*)$', serve, {'document_root': settings.MEDIA_ROOT}, name='media'),

在settings.py中进行配置：

import osMEDIA_ROOT = os.path.join(BASE_DIR, 'media')
MEDIA_URL = "/media/"

在浏览器上访问这个地址：

案例：混合数据（form）

from django.shortcuts import HttpResponse, render
from django import forms
from app01.utils.bootstrap import BootStrapForm
import os
from app01 import models
from django.conf import settingsdef upload_list(request):if request.method == 'GET':return render(request, 'upload_list.html')# 'username': ['lingze']# print(request.POST)  # 请求体中数据# {'avatar': [<InMemoryUploadedFile: 1.png (image/png)>]}# print(request.FILES)   # 请求发过来的文件file_object = request.FILES.get("avatar")print(file_object.name)f = open(file_object.name, mode='wb')for chunk in file_object.chunks():f.write(chunk)f.close()return HttpResponse("....")class UpForm(BootStrapForm):bootstrap_exclude_fields = ['img']name = forms.CharField(label="姓名")age = forms.IntegerField(label="年龄")img = forms.FileField(label="头像")def upload_form(request):title = "Form上传"if request.method == 'GET':form = UpForm()return render(request, 'upload_form.html', {'title': title, 'form': form})form = UpForm(data=request.POST, files=request.FILES)if form.is_valid():# {'name': '吴佩琦2', 'age': 19, 'img': <InMemoryUploadedFile: apple.png (image/png)>}# print(form.cleaned_data)# 1、读取图片内容，写入到文件夹中并获取文件的路径。image_object = form.cleaned_data.get("img")# media_path = os.path.join(settings.MEDIA_ROOT, image_object.name)media_path = os.path.join("media", image_object.name)# db_file_path = os.path.join("static", "img", image_object.name)# file_path = os.path.join("app01", "static", "img", image_object.name)f = open(media_path, 'wb')for chunk in image_object.chunks():f.write(chunk)f.close()# 2、将图片文件路径写入到数据库models.Boss.objects.create(name=form.cleaned_data.get("name"),age=form.cleaned_data.get("age"),img=media_path,)return HttpResponse("...")return render(request, 'upload_form.html', {'title': title, 'form': form})

案例：混合数据（ModelForm）

models.py

class City(models.Model):""" 老板 """name = models.CharField(max_length=32, verbose_name='名称')count = models.IntegerField(verbose_name='人口')# 本质上数据库也是ChartField，自动保存数据。img = models.FileField(max_length=128, verbose_name='Logo', upload_to='city/')

定义ModelForm

from app01.utils.bootstrap import BootStrapForm, BootStrapModelFormclass UpModelForm(BootStrapModelForm):bootstrap_exclude_fields = ['img']class Meta:model = models.Cityfields = '__all__'

视图

def upload_modal_form(request):""" 上传文件和数据（ModalForm）"""title = "ModelForm上传文件"if request.method == 'GET':form = UpModelForm()return render(request, 'upload_form.html', {'form': form, 'title': title})form = UpModelForm(data=request.POST, files=request.FILES)if form.is_valid():# 对于文件：自动保存# 字段 + 上传路径写入到数据库form.save()return HttpResponse("成功")return render(request, 'upload_form.html', {'form': form, 'title': title})

小结

• 自己手动去写

  file_object = request.FILES.get("exc")
  ...
  

• Form组件（表单验证）

  request.POST
  file_object = request.FILES.get("exc")具体文件操作还是手动自己做。
  

• ModelForm（表单验证+自动保存数据库+自动保存文件）

  - Media文件夹
  - Models.py定义类文件要img = models.FileField(verbose_name="Logo", max_length=128, upload_to='city/')