Web框架本质##
web系统概念
1. Http，无状态，短连接
2. 浏览器（socket客户端）、网站（socket服务端）
web框架本质
import socket
def handle_request(client):
buf = client.recv(1024)
client.send("HTTP/1.1 200 OK\r\n\r\n")
client.send("Hello, Seven")
def main():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.bind(('localhost',8000))
sock.listen(5)
while True:
connection, address = sock.accept()
handle_request(connection)
connection.close()
if __name__ == '__main__':
main()
自定义Web框架
a. socket服务端
b. 根据URL不同返回不同的内容
路由系统：
URL -> 函数
c. 字符串返回给用户
模板引擎渲染：
HTML充当模板（特殊字符）
自己创造任意数据
字符串
- 静态网站处理方式：
import socket
def f1(request):
"""
处理用户请求，并返回相应的内容
:param request: 用户请求的所有信息
:return:
"""
f = open('index.fsw','rb')
data = f.read()
f.close()
return data
def f2(request):
f = open('aricle.tpl','rb')
data = f.read()
f.close()
return data
routers = [
('/xxx', f1),
('/ooo', f2),
]
def run():
sock = socket.socket()
sock.bind(('127.0.0.1',8080))
sock.listen(5)
while True:
conn,addr = sock.accept() # hang住
# 有人来连接了
# 获取用户发送的数据
data = conn.recv(8096)
data = str(data,encoding='utf-8')
headers,bodys = data.split('\r\n\r\n')
temp_list = headers.split('\r\n')
method,url,protocal = temp_list[0].split(' ')
conn.send(b"HTTP/1.1 200 OK\r\n\r\n")
func_name = None
for item in routers:
if item[0] == url:
func_name = item[1]
break
if func_name:
response = func_name(data)
else:
response = b"404"
conn.send(response)
conn.close()
if __name__ == '__main__':
run()
- 动态网站处理方式一（手动进行替换的模版引擎）：
import socket
def f3(request):
import pymysql
# 创建连接,获得数据
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123',db='db666')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('select id,username,password from userinfo')
user_list = cursor.fetchall()
cursor.close()
conn.close()
# 组装数据模型
content_list=[]
for row in user_list:
tp = '<tr><td>%s</td><td>%s</td><td>%s</td></tr>'%(row['id'],row['username'],row['password'])
content_list.append(tp)
content = "".join(content_list) # 将列表中的数据拼接成字符串
# 模板渲染（模板+数据）
f = open('userlist.html','r',encoding='utf-8')
template = f.read()
f.close()
data = template.replace('@@sdfsdffd@@', content)
return bytes(data, encoding='utf-8')
# 路由系统
routers = [
('/userlist.htm', f3),
]
def run():
sock = socket.socket()
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(('127.0.0.1',8080))
sock.listen(5)
while True:
conn,addr = sock.accept() # hang住
# 有人来连接了
# 获取用户发送的数据
data = conn.recv(8096)
data = str(data,encoding='utf-8')
headers,bodys = data.split('\r\n\r\n')
temp_list = headers.split('\r\n')
method,url,protocal = temp_list[0].split(' ')
conn.send(b"HTTP/1.1 200 OK\r\n\r\n")
func_name = None
for item in routers:
if item[0] == url:
func_name = item[1]
break
if func_name:
response = func_name(data)
else:
response = b"404"
conn.send(response)
conn.close()
if __name__ == '__main__':
run()
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<table border="1">
<thead>
<tr>
<th>ID</th>
<th>用户名</th>
<th>邮箱</th>
</tr>
</thead>
<tbody>
@@sdfsdffd@@
</tbody>
</table>
</body>
</html>
动态网站二（使用jinjia2模板引擎进行替换）
import socket
def f4(request):
import pymysql
# 创建连接
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='db666')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute("select id,username,password from userinfo")
user_list = cursor.fetchall()
cursor.close()
conn.close()
f = open('hostlist.html','r',encoding='utf-8')
data = f.read()
f.close()
# 基于第三方工具实现的模板渲染
from jinja2 import Template
template = Template(data)
data = template.render(xxxxx=user_list, user='dsafsdfsdf')
return data.encode('utf-8')
# 路由系统
routers = [
('/host.html', f4),
]
def run():
sock = socket.socket()
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(('127.0.0.1',8080))
sock.listen(5)
while True:
conn,addr = sock.accept() # hang住
# 有人来连接了
# 获取用户发送的数据
data = conn.recv(8096)
data = str(data,encoding='utf-8')
headers,bodys = data.split('\r\n\r\n')
temp_list = headers.split('\r\n')
method,url,protocal = temp_list[0].split(' ')
conn.send(b"HTTP/1.1 200 OK\r\n\r\n")
func_name = None
for item in routers:
if item[0] == url:
func_name = item[1]
break
if func_name:
response = func_name(data)
else:
response = b"404"
conn.send(response)
conn.close()
if __name__ == '__main__':
run()
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<table border="1">
<thead>
<tr>
<th>ID</th>
<th>用户名</th>
<th>邮箱</th>
</tr>
</thead>
<tbody>
{% for row in xxxxx %}
<tr>
<td>{{row.id}}</td>
<td>{{row.username}}</td>
<td>{{row.password}}</td>
</tr>
{% endfor %}
</tbody>
</table>
{{user}}
</body>
</html>
Django框架基础内容
框架种类
- a,b,c --> Tornado
- [第三方a],b,c --> wsgiref -> Django
- [第三方a],b,[第三方c] --> flask,
Django项目前期配置
pip3 install django
# 创建Django程序
django-admin startproject mysite
# 进入程序目录
cd mysite
# 启动socket服务端，等待用户发送请求
python manage.py runserver 127.0.0.1:8080
Django配置文件：settings.py
……
DIRS': [os.path.join(BASE_DIR, 'template')],
……
Mysql数据库：
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME':'dbname',
'USER': 'root',
'PASSWORD': 'xxx',
'HOST': '',
'PORT': '',
}
}
#备注：
# 由于Django内部连接MySQL时使用的是MySQLdb模块，而python3中还无此模块，所以需要使用pymysql来代替
# 如下设置放置的与project同名的配置的 __init__.py文件中
import pymysql
pymysql.install_as_MySQLdb()
静态文件路径：
static目录
STATIC_URL = '/static/'
STATICFILES_DIRS = (
os.path.join(BASE_DIR,'static'),
)
额外配置（跨站请求伪装crsf）:
MIDDLEWARE = [
……
#'django.middleware.csrf.CsrfViewMiddleware',
……
]
项目案例
- 网站请求
# urls.py
urlpatterns = [
# url(r'^admin/', admin.site.urls),
url(r'^index/',index),
]
def index(request):
# return HttpResponse('Index')
return render(request, 'index.html',{
'name': 'tom',
'users':['李志','李杰'],
'user_dict':{'k1':'v1', 'k2':'v2'},
'user_list_dict':[
{'id':1,'name':'tom','email':'tom@1231.com'},
{'id':1,'name':'tom','email':'tom@1231.com'},
{'id':1,'name':'tom','email':'tom@1231.com'},
{'id':1,'name':'tom','email':'tom@1231.com'},
]
})
# template/index
<p>{{ name }}</p>
<p>{{ users.0 }}</p>
<p>{{ users.1 }}</p>
<p>{{ user_dict.k1 }}</p>
<p>{{ user_dict.k2 }}</p>
<h3>循环</h3>
<ul>
{% for item in users %}
<li>{{ item }}</li>
{% endfor %}
</ul>
<h3>循环</h3>
<table border="1">
{% for row in user_list_dict %}
<tr>
<td>{{ row.id }}</td>
<td>{{ row.name }}</td>
<td>{{ row.email }}</td>
<td>
<a>编辑</a> | <a href="/del/?nid={{ row.id }}">删除</a>
</td>
</tr>
{% endfor %}
</table>
- 网站登陆
# urls
from django.conf.urls import url
from django.contrib import admin
from django.shortcuts import HttpResponse,render,redirect
urlpatterns = [
# url(r'^admin/', admin.site.urls),
url(r'^login/',login),
]
def login(request):
"""
处理用户请求，并返回内容
:param request: 用户请求相关的所有信息（对象）
:return:
"""
# 字符串
# return HttpResponse('<input type="text" />')
# return HttpResponse('login.html')
# 自动找到模板路径下的login.html文件，读取内容并返回给用户
# 模板路径的配置
print(request.GET) # 结果为字典格式，值为列表类型
if request.method == "GET":
return render(request,'login.html')
else:
# 用户POST提交的数据（请求体）
u = request.POST.get('user')
p = request.POST.get('pwd')
if u == 'root' and p == '123':
# 登录成功
# return redirect('http://www.oldboyedu.com')
return redirect('/index/') # 重定向
else:
# 登录失败
return render(request,'login.html',{'msg': '用户名或密码错误'})
# template
<form method="POST" action="/login/">
<input type="text" name="user" />
<input type="password" name="pwd" />
<input type="submit" value="登录" />
{{ msg }}
</form>
django学员管理系统
数据库设计结构
表结构：班级\学生\老师
（班级表）：
id title
1 全4期
2 全5期
（学生表）：
id name 班级ID（FK）
1 张杰 1
（老师表）：
id name
1 林峰
2 林狗
3 苑天
（老师班级关系表）：
id 老师ID 班级ID
1 1 1
2 1 2
3 2 2
班级管理模块
- 查(母版继承)
# urls
urlpatterns = [
# url(r'^admin/', admin.site.urls),
url(r'classes/', views.classes),
]
# view
from django.shortcuts import render,redirect
import pymysql
def classes(request):
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', password='123', db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor) # 设置查询结果为字典格式
cursor.execute("select id, title from class")
class_list = cursor.fetchall() # 结果为字典
cursor.close()
conn.close()
print(class_list)
return render(request, 'classes.html',{'class_list':class_list})
# html
{% extends ‘manage.html’% } # 继承母版
{%block content%} # 母版块中填充内容
<h1>班级列表</h1>
<div>
<a href="/add_class/">添加</a>
</div>
<table>
<thead>
<tr>
<th>ID</th>
<th>班级名称</th>
<th>操作</th>
</tr>
</thead>
<tbody>
{% for row in class_list %}
<tr>
<td>{{ row.id }}</td>
<td>{{ row.title }}</td>
<td>
<a href="">编辑</a>
|
<a href="">删除</a>
</td>
</tr>
{% endfor %}
</tbody>
</table>
｛% endbloc %}
- 增
# urls
urlpatterns = [
# url(r'^admin/', admin.site.urls),
url(r'^add_class/', views.add_class),
]
# view
def add_class(request):
if request.method == 'GET':
return render(request,'add_class.html')
else:
print(request.POST)
v = request.POST.get('title')
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd='123',db='s4db65',charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('insert into class(title) value(%s)', [v,])
conn.commit() # 提交事务
cursor.close()
conn.close()
return redirect('/classes/')
# html
<h1>添加班级</h1>
<form method="post" action="/add_class/">
<p>班级名称：<input type="text" name="title" /></p>
<input type="submit" value="提交">
</form>
- 删
# urls
urlpatterns = [
url(r'^del_class/', views.del_class),
]
# view
def del_class(request):
nid = request.GET.get('nid')
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('delete from class where id=%s',[nid,])
conn.commit()
cursor.close()
conn.close()
return redirect('/classes/')
- 改
# urls
urlpatterns = [
url(r'^edit_class/', views.edit_class),
]
# view
def edit_class(request):
if request.method == 'GET': # 获取数据
nid = request.GET.get('nid')
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd = '123', db='s4db65',charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('select id, title from class where id=%s', [nid,])
result = cursor.fetchone()
cursor.close()
conn.close()
print(result)
return render(request,'edit_class.html',{'result':result})
else:
nid = request.GET.get('nid')
title = request.POST.get('title')
print(nid, title)
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd='123',db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('update class set title=%s where id=%s',[title,nid,])
conn.commit()
cursor.close()
conn.close()
return redirect('/classes/')
- 模态对话框实现增加班级功能
# html
<a onclick="showModal()">对话框添加</a>
<div id="shadow" class="shadow hide"></div>
<div id="modal" class="model hide">
<p>
<input type="text" id="title">
</p>
<input type="button" value="提交" onclick="AjaxSend()"/><span id=""></span>
<input type="button" value="取消" onclick="cancleModal()">
</div>
# css
.hide {
display: none;
}
.shadow {
position: fixed;
left: 0;
top: 0;
right: 0;
bottom: 0;
background-color: black;
opacity: 0.5;
z-index: 999;
}
.model {
z-index: 1000;
position: fixed;
height: 300px;
width: 400px;
background: white;
left: 50%;
top: 50%;
margin-left: -200px;
margin-top: -150px;
}
# js
function showModal() {
document.getElementById('shadow').classList.remove('hide')
document.getElementById('modal').classList.remove('hide')
}
function cancleModal() {
document.getElementById('shadow').classList.add('hide');
document.getElementById('modal').classList.add('hide');
}
function AjaxSend() {
$.ajax({
url: '/modal_add_class/',
type: 'POST',
data: {'title': $('#title').val()},
success: function (data) {
console.log(data);
if (data == 'ok') {
location.href = '/classes';
} else {
$('errormsg').text(data);
}
}
})
}
# urls
urlpatterns = [url(r'^modal_add_class/', views.modal_add_class]
# views
sqlheper工具类（将增删改查进行封装）：
def modify(sql,args):
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute(sql,args)
conn.commit()
cursor.close()
conn.close()
----------
def modal_add_class(request):
title = request.POST.get('title')
if len(title) > 0:
sqlheper.modify('insert into class (title) value(%s)',[title,])
return HttpResponse('ok')
else:
return HttpResponse('班级标题不能为空')
学生管理模块
- 查
# urls
url(r'^students/',views.students),
# views
def students(request):
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd='123',db='s4db65',charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('select student.id,student.name,class.title from student left JOIN class on student.class_id = class.id')
student_list = cursor.fetchall()
cursor.close()
conn.close()
print('结果：',student_list)
return render(request,'students.html',{'student_list':student_list})
# html
<h1>学生列表</h1>
<div><a href="/add_student/">添加</a></div>
<table>
<thead>
<tr>
<th>ID</th>
<th>学生姓名</th>
<th>所属班级</th>
<th>操作</th>
</tr>
</thead>
<tbody>
{% for row in student_list %}
<tr>
<td>{{ row.id }}</td>
<td>{{ row.name }}</td>
<td>{{ row.title }}</td>
<td>
<a href=" ">编辑</a>
<a>删除</a>
</td>
</tr>
{% endfor %}
</tbody>
</table>
- 增
# urls
url(r'^add_student/',views.add_student)
# views
def add_student(request):
if request.method == 'GET': #只负责跳转页面
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd='123',db='s4db65',charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('select id,title from class')
class_list = cursor.fetchall()
cursor.close()
conn.close()
return render(request,'add_student.html',{'class_list':class_list})
else:
name = request.POST.get('name') #负责提交数据的跳转页面
class_id = request.POST.get('class_id')
conn = pymysql.connect(host='127.0.0.1',port=3306,user='root',passwd='123',db='s4db65',charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute('insert into student(name,class_id)values(%s,%s)',[name,class_id,])
conn.commit()
cursor.close()
conn.close()
return redirect('/students/')
# html
<h1>添加学生</h1>
<form method="post" action="/add_student/">
<p>学生姓名<input type="text" name="name"> </p>
<p>
所属班级
<select name='class_id'>
{% for row in class_list %}
<option value="{{ row.id }}">{{ row.title }}</option>
{% endfor %}
</select>
</p>
<input type="submit" value="提交" />
</form>
- 改
# urls
url(r'^edit_student/',views.edit_student),
# views
from utils import sqlheper
def edit_student(request):
if request.method == "GET":
nid = request.GET.get('nid')
class_list = sqlheper.get_list("select id,title from class",[])
current_student_info = sqlheper.get_one('select id,name,class_id from student where id=%s',[nid,])
print('结果：',class_list,current_student_info,nid)
return render(request,'edit_student.html',{'class_list': class_list,'current_student_info':current_student_info})
else:
nid = request.GET.get('nid')
name = request.POST.get('name')
class_id = request.POST.get('class_id')
sqlheper.modify('update student set name=%s,class_id=%s where id=%s',[name,class_id,nid,])
return redirect('/students/')
# html
<h1>编辑学生</h1>
<form method="post" action="/edit_student/?nid={{ current_student_info.id }}">
<p>学生姓名<input type="text" name="name" value="{{ current_student_info.name }}"></p>
<p>
所属班级
<select name="class_id">
{% for row in class_list %}
{% if row.id == current_student_info.class_id %}
<option selected="selected" value="{{ row.id }}">{{ row.title }}</option>
{% else %}
<option value="{{ row.id }}">{{ row.title }}</option>
{% endif %}
{% endfor %}
</select>
</p>
<input type="submit" value="提交"/>
</form>
- 模态对话框实现增
# html
<div class="shadow hide" id="shadow"></div>
<div class="add-Modal hide" id="addModal">
<p> 姓名：<input id="addName" type="text" name="name" placeholder="姓名" /></p>
<p>班级：
<select id="addClassId" name="classId">
{% for row in class_list %}
<option value="{{ row.id }}">{{ row.title}}</option>
{% endfor %}
</select>
</p>
<p>
<input id="btnAdd" type="button" value="添加" />
<input id="btnCancle" type="button" value="取消" />
</p>
<span id="addError" style="color: red"></span>
</div>
# css
.shadow{
position: fixed;
top: 0;
bottom:0;
left:0;
right: 0;
background-color: black;
opacity: 0.5;
z-index: 999;
}
.add-Modal{
position: fixed;
top:50%;
left:50%;
width: 400px;
height: 300px;
z-index: 1000;
background-color: white;
margin-left: -200px;
margin-top: -200px;
}
.hide{
display: none;
}
# js
$(function(){
$('#addModal_window').click(function(){
$('#shadow,#addModal').removeClass('hide');
});
$('#btnCancle').click(function(){
$('#shadow,#addModal').addClass('hide');
});
$('#btnAdd').click(function () {
$.ajax({
url: '/modal_add_student/',
type: 'POST',
data:{'name':$('#addName').val(),'class_id':$('#addClassId').val()},
success:function (arg) {
arg = JSON.parse(arg);
if(arg.status){
location.reload();
}else {
$('#addError').text(arg.message);
}
}
})
})
# urls
url(r'^modal_add_student/', views.modal_add_student),
# views
def modal_add_student(request):
ret = {'status':True,'message':None}
try:
name = request.POST.get('name')
print('result',name)
class_id = request.POST.get('class_id')
sqlheper.modify('insert into student (name,class_id)values(%s,%s)',[name,class_id,])
except Exception as e:
ret['status']=False
ret['message']=str[e]
return HttpResponse(json.dumps(ret))
- 模态对话框实现改
# html
……
<a class="btn-edit">对话框编辑</a>
……
<div id="editModal" class="add-Modal hide">
<h3>编辑学生信息</h3>
<p>
姓名：<input type="text" name="name" id="editName" placeholder="姓名">
<input type="text" id="editId" style="display: none" />
</p>
<p> 班级：
<select id="editClassId" name="classId">
{% for row in class_list %}
<option value="{{ row.id }}">{{ row.title }}</option>
{% endfor %}
</select>
</p>
<p>
<input id="btnEdit" type="button" value="更新" />
<input id="btnEditCancle" type="button" value="取消" />
</p>
<span id="editError" style="color: red;"></span>
</div>
# css
.shadow{
position: fixed;
top: 0;
bottom:0;
left:0;
right: 0;
background-color: black;
opacity: 0.5;
z-index: 999;
}
.add-Modal{
position: fixed;
top:50%;
left:50%;
width: 400px;
height: 300px;
z-index: 1000;
background-color: white;
margin-left: -200px;
margin-top: -200px;
}
.hide{
display: none;
}
# js
$('.btn-edit').click(function () { #显示数据
$('#shadow,#editModal').removeClass('hide');
var tds = $(this).parent().prevAll();
var studentId = $(tds[2]).text();
var studentName = $(tds[1]).text();
var classId = $(tds[0]).attr('clsid');
console.log(studentId,studentName,classId)
$('#editId').val(studentId);
$('#editName').val(studentName);
$('#editClassId').val(classId);
});
$('#btnEditCancle').click(function () {
$('#shadow,#editModal').addClass('hide');
})
$('#btnEdit').click(function(){ #提交数据
$.ajax({
url:'/modal_edit_student/',
type: 'POST',
data: {'nid': $('#editId').val(), 'name':$('#editName').val(),'class_id': $('#editClassId').val()},
dataType: 'JSON', //JSON.parse(arg)
success:function(arg){
if(arg.status){
location.reload();
}else{
$('#editError').text(arg.message);
}
}
})
})
})
# urls
url(r'^modal_edit_student/', views.modal_edit_student),
# views
def modal_edit_student(request):
ret = {'status': True,'message': None}
try:
nid = request.POST.get('nid')
name = request.POST.get('name')
class_id = request.POST.get('class_id')
sqlheper.modify('update student set name=%s,class_id=%s where id=%s',[name,class_id,nid,])
except Exception as e:
ret['status'] = False
ret['message'] = str(e)
return HttpResponse(json.dumps(ret))
老师管理模块
- 查
# urls
url(r'^teachers/', views.teachers),
# views
# 多对多，以老师表展示
def teachers(request):
teacher_list = sqlheper.get_list('select id,name from teacher',[])
teacher_list = sqlheper.get_list("""
select teacher.id as tid,teacher.name,class.title from teacher
LEFT JOIN teacher2class on teacher.id = teacher2class.teacher_id
left JOIN class on class.id = teacher2class.class_id;
""",[])
print(teacher_list)
result = {}
for row in teacher_list:
tid =row['tid']
if tid in result:
result[tid]['titles'].append(row['title'])
else:
result[tid] = {'tid': row['tid'],'name':row['name'],'titles': [row['title'],]}
return render(request,'teacher.html',{'teacher_list':result.values()})
# html
<table border="1">
<thead>
<tr>
<th>ID</th>
<th>老师姓名</th>
<th>任教班级</th>
<th>操作</th>
</tr>
</thead>
<tbody>
{% for row in teacher_list %}
<tr>
<td>{{ row.tid }}</td>
<td>{{ row.name }}</td>
<td>
{% for item in row.titles %}
<span>{{ item }}</span>
{% endfor %}
</td>
<td>
<a href="/edit_teacher/?nid={{ row.tid }}">编辑</a>
<a>删除</a>
</td>
</tr>
{% endfor %}
</tbody>
</table>
- 增
# ursl
url(r'^add_teacher/', views.add_teacher),
# views
def add_teacher(request):
if request.method == "GET":
class_list = sqlheper.get_list('select id,title from class',[])
return render(request,'add_teacher.html',{'class_list': class_list})
else:
name = request.POST.get('name')
# 老师表中添加一条数据
teacher_id = sqlheper.create('insert into teacher(name) values(%s)',[name,])
# 老师和班级关系表中插入数据
class_ids = request.POST.getlist('class_ids')
# 一次连接，一次提交
data_list = []
for cls_id in class_ids:
temp = (teacher_id,cls_id,)
data_list.append(temp)
obj = sqlheper.SqlHelper() # 通过自定义的mysql组件获得mysql连接对象
obj.multiple_modify('insert into teacher2class(teacher_id,class_id) values(%s,%s)',data_list)
obj.close()
return redirect('/teachers/')
# html
<h1>添加老师</h1>
<form method="POST" action="/add_teacher/">
<p><input type="text" name="name" placeholder="老师姓名" /></p>
<p>
<select multiple size="10" name="class_ids">
{% for item in class_list %}
<option value="{{ item.id }}">{{ item.title }}</option>
{% endfor %}
</select>
</p>
<input type="submit" value="提交" />
</form>
- 改
# html
<h1>编辑老师</h1>
<form method="POST" action="/edit_teacher/?nid={{ teacher_info.id }}">
<p><input type="text" name="name" value="{{ teacher_info.name }}" /></p>
<p>
<select name="class_ids" multiple size="10">
{% for item in class_list %}
{% if item.id in class_id_list %}
<option value="{{ item.id }}" selected>{{ item.title }}</option>
{% else %}
<option value="{{ item.id }}">{{ item.title }}</option>
{% endif %}
{% endfor %}
</select>
</p>
<input type="submit" value="提交" />
</form>
# urls
url(r'^edit_teacher/',views.edit_teacher),
# views
def edit_teacher(request):
if request.method == "GET":
nid = request.GET.get('nid')
obj = sqlheper.SqlHelper()
teacher_info = obj.get_one('select id,name from teacher where id =%s',[nid,])
class_id_list = obj.get_list('select class_id from teacher2class where teacher_id=%s',[nid,])
class_list = obj.get_list('select id,title from class',[])
obj.close()
print('当前老师信息',teacher_info)
print('当前老师任教的班级id',class_id_list)
temp = []
for i in class_id_list:
temp.append(i['class_id'])
print('所有班级',class_list)
# return HttpResponse('...')
return render(request,'edit_teacher.html',{
'teacher_info': teacher_info,
'class_id_list': temp,
'class_list': class_list,
})
else:
nid = request.GET.get('nid')
name = request.POST.get('name')
class_ids = request.POST.getlist('class_ids')
obj = sqlheper.SqlHelper()
# 更新老师表
obj.modify('update teacher set name=%s where id=%s',[name,nid])
# 更新老师和班级关系表
# 先把当前老师和班级的对应关系删除，然后再添加
obj.modify('delete from teacher2class where teacher_id=%s',[nid,])
data_list = []
for cls_id in class_ids:
temp = (nid,cls_id,)
data_list.append(temp)
obj = sqlheper.SqlHelper()
obj.multiple_modify('insert into teacher2class(teacher_id,class_id) values(%s,%s)',data_list)
obj.close()
return redirect('/teachers/')
- 模态对话框增
# html
<div id="shadow" class="shadow hide"></div>
<div id="addModal" class="addModal hide">
<p>老师姓名:<input type="text" name="name" id="addName"></p>
<p>
<select id="classIds" multiple="multiple" size="10">
</select>
</p>
<input type="button" id="addSubmit" value="提交">
<input type="button" id="cancle" value="取消">
</div>
# css
.shadow{
position: fixed;
top:0;
bottom: 0;
left:0;
right: 0;
background-color: black;
opacity: 0.5;
z-index: 999;
}
.addModal{
position: fixed;
width: 400px;
height: 300px;
top:50%;
left:50%;
margin-left: -200px;
margin-top: -200px;
background-color: white;
z-index: 1000;
}
.hide{
display: none;
}
# js
$(function () {
bindAdd();
bindAddSubmit();
});
function bindAdd() {
$('#btnAdd').click(function () {
$('#shadow,#addModal').removeClass('hide');
$.ajax({
url:'/get_all_class/',
type:'GET',
dataType:'JSON',
success:function (arg) {
$.each(arg,function(i,row){
var tag = document.createElement('option');
tag.innerHTML = row.title;
tag.setAttribute('value',row.id);
$('#classIds').append(tag);
});
}
})
});
$('#cancle').click(function () {
$('#shadow,#addModal').addClass('hide');
})
}
function bindAddSubmit(){
$('#addSubmit').click(function(){
var name = $('#addName').val();
var class_id_list = $('#classIds').val();
console.log(name,class_id_list);
$.ajax({
url:'/modal_add_teacher/',
type: 'POST',
data: {'name':name, 'class_id_list': class_id_list},
dataType:'JSON',
traditional: true,// 如果提交的数据的值有列表，则需要添加此属性
success: function (arg) {
if(arg.status){
location.reload();
}else{
alert(arg.message);
}
}
})
});
}
# urls
url(r'^get_all_class/', views.get_all_class),
url(r'^modal_add_teacher/', views.modal_add_teacher),
# views
def get_all_class(request):
obj = sqlheper.SqlHelper()
class_list = obj.get_list('select id,title from class',[])
return HttpResponse(json.dumps(class_list))
def modal_add_teacher(request):
ret = {'status': True,'message': None}
try:
name = request.POST.get('name')
class_id_list = request.POST.getlist('class_id_list')
teacher_id = sqlheper.create('insert into teacher(name) values(%s)',[name,])
data_list = []
for cls_id in class_id_list:
temp = (teacher_id,cls_id,)
data_list.append(temp)
obj = sqlheper.SqlHelper()
obj.multiple_modify('insert into teacher2class(teacher_id,class_id) values(%s,%s)',data_list)
obj.close()
except Exception as e:
ret['status'] = False
ret['message'] = "处理失败"
return HttpResponse(json.dumps(ret))
# sqlheper
def create(sql,args):
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute(sql,args)
conn.commit()
last_row_id = cursor.lastrowid
cursor.close()
conn.close()
return last_row_id
class SqlHelper(object):
def __init__(self):
self.connect() # 读取配置文件
def connect(self):
self.conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='s4db65', charset='utf8')
self.cursor = self.conn.cursor(cursor=pymysql.cursors.DictCursor)
def multiple_modify(self,sql,args):
self.cursor.executemany(sql,args)
self.conn.commit()
def close(self):
self.cursor.close()
self.conn.close()
BOOTSTRAP框架
- bootstrap
下载
导入项目
<link rel="stylesheet" href="/static/plugins/bootstrap-3.3.7-dist/css/bootstrap.css">
根据网站内容，添加对应class标签
fontawesome:同上
后台管理布局(HTML母版)
# manage.html
<head>
<meta charset="UTF-8">
<title></title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.3.7-dist/css/bootstrap.css" />
<link rel="stylesheet" href="/static/plugins/font-awesome-4.7.0/css/font-awesome.css" />
<link rel="stylesheet" href="/static/css/commons.css" />
{% block css %}{% endblock %}
</head>
<body>
<div class="pg-header">
<div class="logo left">老男孩后台管理</div>
<div class="avatar right" style="position: relative">
[外链图片转存失败(img-4ly4Y20a-1562038376731)(https://mp.csdn.net/static/images/1.jpg)]
<div class="user-info">
<a>个人资料</a>
<a>注销</a>
</div>
</div>
<div class="rmenus right">
<a><i class="fa fa-commenting-o" aria-hidden="true"></i> 消息</a>
<a><i class="fa fa-envelope-o" aria-hidden="true"></i> 邮件</a>
</div>
</div>
<div class="pg-body">
<div class="menus">
<a> <i class="fa fa-futbol-o" aria-hidden="true"></i> 班级管理</a>
<a>学生管</a>
<a>老师管理</a>
</div>
<div class="content">
<ol class="breadcrumb">
<li><a href="#">首页</a></li>
<li><a href="#">班级管理</a></li>
<li class="active">添加班级</li>
</ol>
{% block xx %}{% endblock %}
</div>
</div>
{% block js %}{% endblock %}
# css
body{
margin: 0;
}
.left{
float: left;
}
.right{
float: right;
}
.hide{
display: none;
}
.pg-header{
height: 48px;
min-width: 1190px;
background-color: #204d74;
line-height: 48px;
}
.pg-header .logo{
color: white;
font-size: 18px;
width: 200px;
text-align: center;
border-right: 1px solid #8a6d3b;
}
.pg-header .rmenus a{
display: inline-block;
padding: 0 15px;
color: white;
}
.pg-header .rmenus a:hover{
background-color: #269abc;
}
.pg-header .avatar{
padding: 0 20px;
}
.pg-header .avatar img{
border-radius: 50%;
}
.pg-header .avatar .user-info{
display: none;
background-color: white;
border: 1px solid #dddddd;
position: absolute;width: 100px;top: 48px;right: 20px;color: white;z-index: 100;
text-align: center;
}
.pg-header .avatar:hover .user-info{
display: block;
}
.pg-header .avatar .user-info a{
display: block;
}
.menus{
width: 200px;
position: absolute;
left: 0;
bottom: 0;
top: 48px;
border-right: 1px solid #dddddd;
background-color: #dddddd;
}
.content{
position: absolute;
left: 200px;
right: 0;
top: 48px;
bottom: 0;
min-width: 990px;
overflow: scroll;
z-index: 99;
}
.pg-body .menus a{
display: block;
padding: 10px 5px;
border-bottom: 1px solid #ffffff;
}
用户登陆(包含cookies内容)
# html
<form method="post" action="/login/">
<input type="text" name="username">
<input type="password" name="password">
<input type="submit" value="提交">
</form>
# urls
url(r'^login/', views.login),
# views
def login(request):
if request.method == "GET":
return render(request,'login.html')
else:
user = request.POST.get('username')
pwd = request.POST.get('password')
if user == 'tom' and pwd == '123':
obj = redirect('/classes/')
obj.set_signed_cookie('ticket',"567",salt='jjjjjj',max_age=900,path='/') # 设置cookies，浏览器的cookies中会直接以明文显示567
return obj
else:
return render(request,'login.html')
def classes(request):
# 去请求的cookie中找凭证
# tk = request.COOKIES.get('ticket')
tk = request.get_signed_cookie('ticket',salt='jjjjjj')
print(tk)
if not tk:
return redirect('/login/')
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='s4db65', charset='utf8')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute("select id,title from class")
class_list = cursor.fetchall()
cursor.close()
conn.close()
return render(request, 'classes.html', {'class_list': class_list})
# 内容延伸
装饰器装饰views中的函数
@xzxx
def index(request):
obj = HttpResponse('...')
obj.set_cookie(.....)
request.COOKIES.get(...)
obj.set_signed_cookie(.....)
request.get_signed_cookie(....)
动态路由
urls
# 动态路由
# url(r'^edit/(\w+)/(\w+)/', views.edit),
# url(r'^edit/(?P<a1>\w+)/(?P<a2>\w+)/', views.edit),
# url(r'^edit/(\w+).html$', views.edit) #正则表达式实现静态伪装
views
def edit(request,*args,**kwargs):#获得请求数据
print(args,kwargs)
return HttpResponse('...')
路由分发
＃路由分发实现不同模块分开编辑，团队协作开发
url(r'^app01/', include('app01.urls')), #不同的程序模块
url(r'^app02/', include('app02.urls')),
# url(r'^', default), # 设置默认页面，接收任意请求
# url(r'^', views.index), #
反向生成URL（Django独有）
通过别名反射成URL，简化URL的填写， 用于权限管理
#urls
url(r'^edit/(\w+)/(\w+)/', views.edit,name='n2'),
# html
<ul>
{% for i in user_list %}
<li>{{ i }} | <a href="/edit/{{ i }}/">编辑</a></li>
<li>{{ i }} | <a href="{% url "n2" i 1 %}">编辑</a></li> # i和1作为url中的参数
{% endfor %}
</ul>
ORM基本操作（数据表+数据行操作）
操作前的配置步骤
__init__.py文件
(ORM默认使用SQLlite连接数据库,需改成Mysql)
添加：
import pymysql
pymysql.install_as_MySQLdb()
在mysql中手动创建数据库
# 配置setting文件中重写数数据库配置
TEMPLATES = [
……
'DIRS': [os.path.join(BASE_DIR,'templates')],
……
]
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME':'s4day70db',
'USER': 'root',
'PASSWORD': '',
'HOST': 'localhost',
'PORT': 3306,
}
}
操作表
- 创建表
# models
from django.db import models
class UserInfo(models.Model): # 在数据库中的表名为模块名_UserInfo
nid = models.BigAutoField(primary_key=True) #可不写，默认会生成表中的id字段
username = models.CharField(max_length=32)
password = models.CharField(max_length=64)
# settings配置文件中安装app01模块
INSTALLED_APPS = [
……
'app01',
]
# 执行语句
python manage.py makemigrations #生成数据表配置文件，包含生成及修改等信息
python manage.py migrate #执行生成的配置文件
- 修改表：
# models
class UserInfo(models.Model):
……
age = models.IntegerField(default=1) # 新增字段时需设置默认值/允许为空
# age = models.IntegerField(null=True)
# 执行语句：
python manage.py makemigrations #生成数据表配置文件，包含生成及修改等信息
python manage.py migrate #执行生成的配置文件
- 删除表：
# 参考修改表
- 创建外键关联：
# models
class UserGroup(models.Model): #等同于主表，需将该类写在子表前面
title = models.CharField(max_length=32)
class UserInfo(models.Model): # 外键所在的表等同于子表
……
ug = models.ForeignKey('UserGroup',null=True,on_delete='') # 外键关联字段关联UserGroup表中的Id字段，ug在UserInfo数据表中的字段为ug_id
- 操作单表数据行：
# 增
from app01 import models
models.UserGroup.objects.create(title='销售部')
# 删
models.UserGroup.objects.filter(id=2).delete()
# 改
models.UserGroup.objects.filter(id=2).update(title='公关部')
# 查
group_list = models.UserGroup.objects.all()
group_list = models.UserGroup.objects.filter(id=1)
group_list = models.UserGroup.objects.filter(id__gt=1) #大于1
group_list = models.UserGroup.objects.filter(id__lt=1) #小于1
Django视图CBV
urls
url(r'^login.html$', views.Login.as_view),
views
from django.views import View
class Login(View): # 继承View类作为父类
# #重写父类方法，该方法可作为装饰器功能
def dispatch(self, request, *args, **kwargs): # 自定制 dispatch方法，除了可以利用父类中原dispatch方法，还可以自定制处理逻辑
print('before')
obj = super(Login,self).dispatch(request, *args, **kwargs) # 传入Login对象作为参数，调用父类中的方法
print('after')
return obj
def get(self,request): # 请求为get请求时，自动调用该方法
# return HttpResponse('Login.get')
return render(request,'login.html')
def post(self,request): # 请求是POST请求时，自动调用该方法
print(request.POST.get('user'))
return HttpResponse('Login.post')
# html(login.html)
<form method="POST" action="/login.html"> # 以POST方式提交，会自动调用post方法
<input type="text" name="user" />
<input type="submit" value="提交" />
</form>
ORM连表操作（一对多）（一对多中，外键存在于从表中）
models
from django.db import models
class UserType(models.Model):
# 用户类型
title = models.CharField(max_length=32)
class UserInfo(models.Model): """
# 用户表
name = models.CharField(max_length=16)
age = models.IntegerField()
ut = models.ForeignKey('UserType',on_delete='') # 关联UserType表中的id字段
urls
url(r'^test.html$', views.test),
views
# 创建数据
# models.UserType.objects.create(title='普通用户')
# models.UserType.objects.create(title='二逼用户')
# models.UserType.objects.create(title='牛逼用户')
# models.UserInfo.objects.create(name='方少伟',age=18,ut_id=1)
# models.UserInfo.objects.create(name='由秦兵',age=18,ut_id=2)
# models.UserInfo.objects.create(name='刘庚',age=18,ut_id=2)
# models.UserInfo.objects.create(name='陈涛',age=18,ut_id=3)
# models.UserInfo.objects.create(name='王者',age=18,ut_id=3)
# models.UserInfo.objects.create(name='杨涵',age=18,ut_id=1)
- 一对多的正向操作（让存在外键的从表进行跨表，去查询关联主表中的字段）：
# 获得Queryset对象格式数据（格式：对象名.外键字段名.关联表字段名）
obj = models.UserInfo.objects.all().first() # 获取一条数据，无需再obj[0]来获取具体的对象
print(obj.name,obj.age,obj.ut.title) # 获取跨表后的字段用obj.ut.title方式，ut是外键关联中的字段
获得查询结果为字典格式组合成列表类型的Queryset数据,可用list方法转换成列表格式（从表中的外键字段名__主表中的字段名）
v1 = models.UserInfo.objects.values('id','name','ut__title')
# 获得查询结果为元组格式组合成列表类型的Queryset数据,可用List转换成列表（从表中的外键字段名__主表中的字段名）
result = models.UserInfo.objects.all().values_list('id','name'.'ut__title')
- 一对多的反向操作(让主表进行跨表，去查询（有外键关联字段）从表中相应的字段作为查询条件或查询结果)：
# 获得Queryset对象格式的数据,(格式：主表的QuerySet对象名.从表名__set.all())
（一个用户类型下可以有很多用户，获得所有用户类型对应的用户信息数据）：
obj = models.UserType.objects.all().first()
for row in obj.userinfo_set.all():
print(row.name,row.age)
# 获得字典格式Queryset对象格式的数据,需要转换成json字符串格式通过ajax返回数据时，可用list方法转换成列表（从表表名小写__主表字段名）
v2 = models.UserType.objects.values('id','title','userinfo__name')
# 获得元组格式Queryset对象格式的数据,需要转换成json字符串格式通过ajax返回数据时，可用list方法转换成列表。（外键字段名__从表字段名）
result = models.UserType.objects.all().values_list('id','name','userinfo__name')
- 一对多其他参考：
# 跨表
# 正向查询：
1. q = UserInfo.objects.all().first()
q.ug.title
2.
UserInfo.objects.values('nid','ug_id')
UserInfo.objects.values('nid','ug_id','ug__title')
3. UserInfo.objects.values_list('nid','ug_id','ug__title')
# 反向查询：
1. 小写的表名_set
obj = UserGroup.objects.all().first()
result = obj.userinfo_set.all() [userinfo对象,userinfo对象,]
2. 小写的表名
v = UserGroup.objects.values('id','title')
v = UserGroup.objects.values('id','title','小写的从表名称')
v = UserGroup.objects.values('id','title','小写的从表名称__age')
3. 小写的表名
v = UserGroup.objects.values_list('id','title')
v = UserGroup.objects.values_list('id','title','小写的表名称')
v = UserGroup.objects.values_list('id','title','小写的表名称__age')
ORM连表操作（多对多）
（多对多中，主表与从表的外键都共同存在于第3张关联表中） ##
手动创建第三张关联表（推荐，手动更灵活）
# models
from django.db import models
class Boy(models.Model):
name = models.CharField(max_length=32)
class Girl(models.Model):
nick = models.CharField(max_length=32)
class Love(models.Model):
b = models.ForeignKey('Boy',on_delete='')
g = models.ForeignKey('Girl',on_delete='')
class Meta: #添加联合唯一字段
unique_together = [
('b','g'),
]
# views
# 添加数据
objs = [
models.Boy(name='方少伟'),
models.Boy(name='由秦兵'),
models.Boy(name='陈涛'),
models.Boy(name='闫龙'),
models.Boy(name='吴彦祖'),
]
models.Boy.objects.bulk_create(objs,5) # 批量添加数据
objss = [
models.Girl(nick='小鱼'),
models.Girl(nick='小周'),
models.Girl(nick='小猫'),
models.Girl(nick='小狗'),
]
models.Girl.objects.bulk_create(objss,5)
# 1. 查询和方少伟有关系的姑娘
# 第一种查询方式：跨表反向查询，获得对象
# obj = models.Boy.objects.filter(name='方少伟').first()
# love_list = obj.love_set.all() # 反向查询，获得所有love表中的对象
# for row in love_list:
# print(row.g.nick) # 获得对应的姑娘数据
# 第二种查询方式：连表查询（正向查询），直接查询love表，获得对象
# love_list = models.Love.objects.filter(b__name='方少伟') #获得Queryset对象
# for row in love_list:
# print(row.g.nick)
# （推荐）第三种查询方式：只发送一次sql连接请求，获得字典,属于正向查询
# love_list = models.Love.objects.filter(b__name='方少伟').values('g__nick')
# for item in love_list: # 获得字典格式的列表，[{'g__nick':'xxx},]
# print(item['g__nick'])
# （推荐）第四种查询方式：相当于inner join方式连表查询，只发送一次sql连接请求，获得对象
# love_list = models.Love.objects.filter(b__name='方少伟').select_related('g')
# for obj in love_list: # 获得对象
# print(obj.g.nick)
# 总结：多对多都是先获得关联表中的数据，再进行跨表操作
# 对象格式用.（点）进行跨表 字典和元组采用_（双下划线）进行跨表
Django自动生成第三张关联表（无法再手动添加其它字段）
# models
class Boy(models.Model):
name = models.CharField(max_length=32)
m = models.ManyToManyField('Girl') #自动生成关联表m，以两张表中的id字段作为关联字段
class Girl(models.Model):
nick = models.CharField(max_length=32)
# views
# 增
# obj = models.Boy.objects.filter(name='方少伟').first()
# obj.m.add(2)
# obj.m.add(2,4) # 创建关联表的多条数据
# obj.m.add(*[1,3]) # 以列表形式创建多条数据
# 删
# obj.m.remove(1)
# obj.m.remove(2,3) # 删除关联表的多条数据
# obj.m.remove(*[4,])
# obj.m.set([1,]) # 覆盖数据库所有数据,重置
# obj = models.Boy.objects.filter(name='方少伟').first()
# obj.m.clear() # 删除所有与方少伟的关联数据
# 查
# 正向查询出单条数据
# obj = models.Boy.objects.filter(name='方少伟').first()
# # girl_list = obj.m.all()
# girl_list = obj.m.filter(nick='小鱼') # 相当于从从表跨表到主表查询
# print(girl_list)
# 反向查询出多条数据
# obj = models.Girl.objects.filter(nick='小鱼').first()
# print(obj.id,obj.nick)
# boy_list = obj.boy_set.all() # 相当于从主表跨表到从表反向查询
手动与自动结合
# models
class Boy(models.Model):
name = models.CharField(max_length=32)
m = models.ManyToManyField(to='Girl',through="Love",through_fields=('b','g',))
# 可不写to关键字
class Girl(models.Model):
nick = models.CharField(max_length=32)
class Love(models.Model):
b = models.ForeignKey('Boy',on_delete='')
g = models.ForeignKey('Girl',on_delete='')
class Meta:
unique_together = [
('b','g'),
]
# views
obj = models.Boy.objects.filter(name='方少伟').first()
obj.m.add(1)
# obj.m.remove(1)
# obj.m.clear() 可以
v = obj.m.all()
print(v)
ORM连表操作（多对多自关联）
原理：等同于复制出一张新表
models
class UserInfo(models.Model):
nickname = models.CharField(max_length=32)
username = models.CharField(max_length=32)
password = models.CharField(max_length=64)
gender_choices = (
(1,'男'),
(2,'女'),
)
gender = models.IntegerField(choices=gender_choices)
m = models.ManyToManyField('UserInfo') # 多对多自关联字段，自动生成第二张表，字段分别为from_userinfo_id和to_userinfo_id;
# 表中的m属性不会在userinfo表中生成m字段
def test(request):
# 查男生（通过m字段查询属于正向操作）
xz = models.UserInfo.objects.filter(id=1).first() #id为1代表男生的1条数据
u = xz.m.all()
for row in u:
print(row.nickname)
# 查女生(通过表名称_set查询属于反向操作)
xz = models.UserInfo.objects.filter(id=4).first() #id为4代表女生的1条数据
v = xz.userinfo_set.all()
for row in v:
print(row.nickname)
return HttpResponse('...')
外键自关联（常用于评论表功能）
等同于复制出一张新表，用原表中的外键作连表操作
class Comment(models.Model):
"""
评论表
"""
news_id = models.IntegerField() # 新闻ID
content = models.CharField(max_length=32) # 评论内容
user = models.CharField(max_length=32) # 评论者
reply = models.ForeignKey('Comment',null=True,blank=True,related_name='xxxx') #related_name表示反向查询时，代替 表名_set 和 表名__字段名
"""
新闻ID reply_id
1 1 别比比 root null
2 1 就比比 root null
3 1 瞎比比 shaowei null
4 2 写的正好 root null
5 1 拉倒吧 由清滨 2
6 1 拉倒吧1 xxxxx 2
7 1 拉倒吧2 xxxxx 5
"""
"""
新闻1
别比比
就比比
- 拉倒吧
- 拉倒吧2
- 拉倒吧1
瞎比比
新闻2：
写的正好
"""
ORM操作补充（models模块中数据表属性定义操作）
models
from django.db import models
from django.core.validators import RegexValidator
class UserAdmin(models.Model):
username = models.CharField(max_length=32)
email = models.EmailField(null=True,default='111',
db_index=True,unique=True,
blank=True,verbose_name='邮箱',
editable=True, help_text='字段提示信息的内容',
)
# blank控制admin是否为空，
file = models.FileField() #文件字段，只针对admin
ctime = models.DateTimeField() # 日期字段
# 自定义正则表达式验证规则
test = models.CharField(
max_length=32,
error_messages={
'c1': '优先错信息1',
},
validators=[RegexValidator(regex='root_\d+', message='错误了', code='c1')],
null=True
)
# 数字及小数
# num = models.FloatField()
# num = models.IntegerField()
num = models.DecimalField(max_digits=30,decimal_places=10) # 总长度为30，小数点后面10位
# 枚举
color_list = (
(1,'黑色'),
(2,'白色'),
(3,'蓝色')
)
color = models.IntegerField(choices=color_list)
class Meta:
unique_together=(
('email','username') # 字段联合唯一索引
)
index_together=(
('email','username') # 联合索引，不做约束限制
)
# admin模块
from django.contrib import admin
from app01 import models
admin.site.register(models.UserAdmin)
分页查询
内置分页函数
- urls
url(r'^index.html$', views.index),
- views
from django.core.paginator import Paginator,Page,PageNotAnInteger,EmptyPage
def index(request):
user_list = models.UserInfo.objects.all() #获得所有数据库数据
paginator = Paginator(user_list,10) #设置每页显示的总条数
current_page = request.GET.get('page')# 获得当前页数
try:
posts = paginator.page(current_page) #设置当前页数对应的数据
except PageNotAnInteger as e: #当前页面数非整数
posts = paginator.page(1)
except EmptyPage as e: #当前页码数为空
posts = paginator.page(1)
return render(request,'index.html',{'posts':posts})
- html
<h1>用户列表</h1>
<ul>
{% for row in posts.object_list %}
<li>{{ row.name }}</li>
{% endfor %}
</ul>
<div>
{% if posts.has_previous %} #是否有上一页
<a href="/index.html?page={{ posts.previous_page_number }}">上一页</a>
{% endif %}
{% if posts.has_next %} #是否有下一页
<a href="/index.html?page={{ posts.next_page_number }}">下一页</a>
{% endif %}
</div>
自定分页
- urls
url(r'^custom.html$', views.custom),
- views
from utils.pager import PageInfo
def custom(request):
all_count = models.UserInfo.objects.all().count()
page_info = PageInfo(request.GET.get('page'),all_count,10,'/custom.html',11)
user_list = models.UserInfo.objects.all()[page_info.start():page_info.end()]
return render(request,'custom.html',{'user_list':user_list,'page_info':page_info})
- PageInfo工具类
class PageInfo(object):
def __init__(self,current_page,all_count,per_page,base_url,show_page=11):
'''
:param current_page:
:param all_count: 数据库总行数
:param per_page: 每页显示行数
:param base_url:
:param show_page:分页码范围，默认为11
'''
try:
self.current_page = int(current_page)
except Exception as e:
self.current_page = 1
self.per_page=per_page
a,b = divmod(all_count,per_page) #返回一个包含商和余数的元组
if b: # 数据库总数/页面总数后还有多余的数据，所以还需要加1页来显示剩余的数据
a = a+1
self.all_pager= a # 总页数
self.show_page= show_page
self.base_url= base_url
# 页码数对应的展示数据内容
def start(self):
return (self.current_page-1) * self.per_page # 起始数据位置
def end(self):
return self.current_page * self.per_page
# 组装分页模块
def pager(self):
page_list=[]
# 计算中间页码数显示起始数和结尾数
half = int((self.show_page-1)/2) # 中间页码数
# 如果数据总页数 < 分页码范围11
if self.all_pager < self.show_page:
begin =1
stop=self.all_pager + 1
# 如果数据总页数 > 分页码范围11
else:
# 如果当前页 <=5,永远显示1,11
if self.current_page <= half:
begin =1
stop = self.show_page + 1
else:
if self.current_page + half > self.all_pager:
begin = self.all_pager - self.show_page + 1
stop = self.all_pager + 1
else:
begin = self.current_page - half
stop = self.current_page + half + 1
# 组装‘上一页’选项
if self.current_page <= 1:
prev = "<li><a href='#'>上一页</a></li>"
else:
prev = "<li><a href='%s?page=%s'>上一页</a></li>"%(self.base_url,self.current_page-1,)
page_list.append(prev)
# 组装中间页码数显示
for i in range(begin, stop):
if i == self.current_page:
temp = "<li class='active'><a href='%s?page=%s'>%s</a></li>" % (self.base_url, i, i,)
else:
temp = "<li><a href='%s?page=%s'>%s</a></li>" % (self.base_url, i, i,)
page_list.append(temp)
# 组装'下一页'选项
if self.current_page >= self.all_pager:
nex = "<li><a href='#'>下一页</a></li>"
else:
nex = "<li><a href='%s?page=%s'>下一页</a></li>" %(self.base_url,self.current_page+1,)
page_list.append(nex)
return ''.join(page_list)
- html
<h1>用户列表</h1>
<ul>
{% for row in user_list %}
<li>{{ row.name }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
{{ page_info.pager|safe }}
</ul>
</nav>
