表单的增 删 改 查

django单表操作 增 删 改 查

 

一、实现：增、删、改、查

1、获取所有数据显示在页面上

model.Classes.object.all()，拿到数据后，渲染给前端;前端通过for循环的方式，取出数据。

目的：通过classes（班级表数据库）里面的字段拿到对应的数据。

2、添加功能

配置url分发路由增加一个add_classes.html页面

写一个def add_classess函数

在前端写一个a标签，前端页面就可以看到一个添加链接，通过点这个a标签的链接跳转到一个新的add_classess页面

add_classess.html 页面中实现两个功能：

form表单 ：返回给add_classess.html页面

input  输入框

input  提交按钮

接下来就要接收前端输入的数据：

if  request.mothod='GET'

elif

 request.mothod='POST'

request.POST.get('title')  拿到传过来的班级数据

然后通过创建的方式，写入对应的title字段数据库中

方法：models.Classes.objects.create(titile=title)

再返回给return redirect('/get_classes.html')

3、删除功能

配置url路由分发

加一个操作：

<th>操作</th>

一个a标签：

<a href="/del_classes.html?nid={{ row.id }}">删除</a>

实现删除操作，就是找到数据库中，对应的id字段(赋值给nid=id)，删除掉这个ID字段这行数据，就实现了删除功能。

4、实现编辑功能

在get_classes.html里添加一个a标签

配置路由分发

写def edit_classes函数

班级这个输入框前面id不显示,因为id不能被用户修改，所以要隐藏。

根据id拿到这个对象（id 走get方法），id存放在请求头中发送过去的。

obj对象里面包含id 和 title ，走post方法，title是放在请求体中发送过去的

第一次：get拿到id

if request.method == 'GET':
        nid = request.GET.get('nid')
        obj = models.Classes.objects.filter(id=nid).first()
        return render(request, 'edit_classes.html', {'obj': obj})

第二次：post拿到id和title

elif request.method == 'POST':
        nid = request.GET.get('nid')
        title = request.POST.get('title')
        models.Classes.objects.filter(id=nid).update(titile=title)
        return redirect('/get_classes.html')

综合应用示例：

models.py

from django.db import models

# Create your models here.

class Classes(models.Model):
    """
    班级表,男
    """
    titile = models.CharField(max_length=32)
    m = models.ManyToManyField("Teachers")

class Teachers(models.Model):
    """
    老师表，女
    """
    name = models.CharField (max_length=32)

"""
cid_id  tid_id
 1    1
 1    2
 6    1
 1000  1000
"""
# class C2T(models.Model):
#     cid = models.ForeignKey(Classes)
#     tid = models.ForeignKey(Teachers)

class Student(models.Model):
    username = models.CharField(max_length=32)
    age = models.IntegerField()
    gender = models.BooleanField()
    cs = models.ForeignKey(Classes)

urls.py

"""django_one URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/1.10/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  url(r'^$', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  url(r'^$', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.conf.urls import url, include
    2. Add a URL to urlpatterns:  url(r'^blog/', include('blog.urls'))
"""
from django.conf.urls import url
from django.contrib import admin
from app01.views import classes

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^get_classes.html$', classes.get_classes),
    url(r'^add_classes.html$', classes.add_classes),
    url(r'^del_classes.html$', classes.del_classes),
    url(r'^edit_classes.html$', classes.edit_classes),

]

classes.py

from django.shortcuts import render
from django.shortcuts import redirect
from app01 import models


def get_classes(request):
    cls_list = models.Classes.objects.all()
    return render(request, 'get_classes.html', {'cls_list': cls_list})


def add_classes(request):
    if request.method == "GET":
        return render(request, 'add_classes.html')
    elif request.method == 'POST':
        title = request.POST.get('titile')
        models.Classes.objects.create(titile=title)
        return redirect('/get_classes.html')


def del_classes(request):
    nid = request.GET.get('nid')
    models.Classes.objects.filter(id=nid).delete()
    return redirect('/get_classes.html')


def edit_classes(request):
    if request.method == 'GET':
        nid = request.GET.get('nid')
        obj = models.Classes.objects.filter(id=nid).first()
        return render(request, 'edit_classes.html', {'obj': obj})
    elif request.method == 'POST':
        nid = request.GET.get('nid')
        title = request.POST.get('title')
        models.Classes.objects.filter(id=nid).update(titile=title)
        return redirect('/get_classes.html')

get_classes.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div>
    <a href="/add_classes.html">添加</a>
</div>
<div>
    <table border="1">
        <thead>
        <tr>
            <th>ID</th>
            <th>名称</th>
            <th>操作</th>
        </tr>
        </thead>
        <tbody>
        {% for row in cls_list %}
            <tr>
                <td>{{ row.id }}</td>
                <td>{{ row.titile }}</td>
                <td>
                    <a href="/del_classes.html?nid={{ row.id }}">删除</a>
                    |
                    <a href="/edit_classes.html?nid={{ row.id }}">编辑</a>
                </td>
            </tr>
        {% endfor %}
        </tbody>
    </table>
</div>
</body>
</html>

add_classes.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="add_classes.html" method="POST">
    {% csrf_token %}
    <input type="text" name="titile" />
    <input type="submit" value="提交" />
</form>
</body>
</html>

edit_classes.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
    <form action="/edit_classes.html?nid={{ obj.id }}" method="POST">
        {% csrf_token %}
    <input type="text" name="title" value="{{ obj.titile }}" />
    <input type="submit" value="提交"/>
</form>
</body>
</html>

项目名:LibraryManager

APP名: APP01:

LibraryManager文件中:

__init__:

import pymysql
pymysql.install_as_MySQLdb()

setting配置:

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    # 'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, 'templates')]
        ,
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'LibraryManager.wsgi.application'


# Database
# https://docs.djangoproject.com/en/1.11/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'library',
        'USER': 'root',
        'PASSWORD': '',
        'HOST': '127.0.0.1',
        'PORT': 3306,
    }
}

STATIC_URL = '/static/'
STATICFILES_DIRS = [
    os.path.join(BASE_DIR,'static')
]

urls.py:

"""LibraryManager URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/1.11/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  url(r'^$', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  url(r'^$', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.conf.urls import url, include
    2. Add a URL to urlpatterns:  url(r'^blog/', include('blog.urls'))
"""
from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^publisher/',views.publisher_list),
    url(r'^add_publisher/',views.add_publisher),
    url(r'^del_publisher/',views.del_publisher),
    url(r'^edit_publisher/',views.edit_publisher),
]

APP01文件中:

admin.py:

from django.contrib import admin

# Register your models here.

apps.py:

from django.apps import AppConfig


class App01Config(AppConfig):
    name = 'app01'

models.py:

from django.db import models


class Publisher(models.Model):
    id = models.AutoField(primary_key=True)
    name = models.CharField(max_length=32,unique=True)

    def __str__(self):
        return self.name

views.py:

from django.shortcuts import render,HttpResponse,redirect
from app01 import models

def publisher_list(request):
    # 从数据库中获取所有的数据:
    publisher_obj_list = models.Publisher.objects.all().order_by('-id')
    return render(request,'publisher_list.html',{'publishers':publisher_obj_list})

# 添加出版社
# def add_publisher(request):
#     add_name,err_msg = '',''
#     if request.method=='POST':
#         add_name = request.POST.get('new_name')
#         pub_list = models.Publisher.objects.filter(name=add_name)
#         if add_name and not pub_list:
#             models.Publisher.objects.create(name=add_name)
#             return redirect('/publisher/')
#         if not add_name:
#             err_msg='不能为空'
#         if pub_list:
#             err_msg='出版社已存在'
#     return render(request,'add_publisher.html',{'err_name':add_name,'err_msg':err_msg})

# 添加出版社
def add_publisher(request):
    if request.method == 'POST':  #选择提交方式
        add_name = request.POST.get('new_name')     #获取新添加的名字赋值给add_name
        if not add_name:  #如果名字不存在为空
            return render(request, 'add_publisher.html', {"err_name": add_name, 'err_msg': '不能为空'})
        pub_list = models.Publisher.objects.filter(name=add_name)  #过滤添加的name在不在Publisher表里
        if pub_list:   # 如果存在表里
            return render(request, 'add_publisher.html',{"err_name":add_name,'err_msg':'出版社已存在'})
        models.Publisher.objects.create(name=add_name)  #创建新内容(相当于前面有个else,函数遇见return结束函数,所以不用写else,如果没有return ,必须写else)
        return redirect('/publisher/')   #返回跳转页面
    return render(request,'add_publisher.html')


 #删除出版社
def del_publisher(request):
    #获取要删除的对象id
    del_id = request.GET.get('id')
    del_list = models.Publisher.objects.filter(id=del_id)#筛选删除的id在Publisher里
    if del_list:
        #删除满足条件的所有对象
        del_list.delete()
        return redirect('/publisher/')
    else:
        return HttpResponse('删除失败')

#编辑出版社
def edit_publisher(request):
    #获取要编辑的对象id
    edit_id = request.GET.get('id')
    edit_list = models.Publisher.objects.filter(id=edit_id)#筛选要编辑的id在Publisher里赋值给左边
    err_msg = ''
    if request.method == 'POST':
        edit_name = request.POST.get('new_name')#获得输入新的出版社的名字
        print(edit_name,type(edit_name))
        check_list = models.Publisher.objects.filter(name=edit_name)#判断在不在原来的表里
        if edit_name and edit_list and not check_list:
            edit_obj = edit_list[0]
            edit_obj.name = edit_name  #新的出版社赋值给要编辑的出版社
            edit_obj.save()    # 保存在数据库中
            return redirect('/publisher/')
        if check_list:
            err_msg = '出版社已存在'
        if not edit_name:
            err_msg = '出版社不能为空'
    if edit_list:
        edit_obj = edit_list[0]     #从表里获取的
        return render(request,'edit_publisher.html',{'old_obj':edit_obj,'err_msg':err_msg})
    else:
        return HttpResponse('数据不存在')

templates文件夹中:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>添加出版社</title>
</head>
<body>
<h1>添加出版社</h1>
<form action="" method="post">
    <p>名称：<input type="text" name="new_name" value="{{ err_name }}"></p><span>{{ err_msg }}</span>
    <button>提交</button>
</form>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>编辑出版社</title>
</head>
<body>
<h1>编辑出版社</h1>
<form action="" method="post">
    <p>名称：<input type="text" name="new_name" value="{{ old_obj.name }}"></p><span>{{ err_msg }}</span>
    <button>提交</button>
</form>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<a href="/add_publisher/">添加出版社</a>
<table border="1">
    <thead>
    <tr>
        <th>序号</th>
        <th>ID</th>
        <th>出版社名称</th>
        <th>操作</th>
    </tr>
    </thead>
    <tbody>
    {% for publisher in publishers %}
        <tr>
            <td>{{ forloop.counter }}</td>
            <td>{{ publisher.id }}</td>
            <td>{{ publisher.name }}</td>
            <td>
                <a href="/del_publisher/?id={{ publisher.id }}"><button>删除</button></a>
                <a href="/edit_publisher/?id={{ publisher.id }}"><button>编辑</button></a>
            </td>
        </tr>
    {% endfor %}
    </tbody>
</table>
</body>
</html>

manage.py:

#!/usr/bin/env python
import os
import sys

if __name__ == "__main__":
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "LibraryManager.settings")
    try:
        from django.core.management import execute_from_command_line
    except ImportError:
        # The above import may fail for some other reason. Ensure that the
        # issue is really that Django is missing to avoid masking other
        # exceptions on Python 2.
        try:
            import django
        except ImportError:
            raise ImportError(
                "Couldn't import Django. Are you sure it's installed and "
                "available on your PYTHONPATH environment variable? Did you "
                "forget to activate a virtual environment?"
            )
        raise
    execute_from_command_line(sys.argv)