def reg(request):errors = {'username':'','password':''}if request.method == 'POST':username = request.POST.get('username')password = request.POST.get('password')if 'sb' in username:errors['username'] = '用户名里面不能有sb，你这个dsb'if password == '123':errors['password'] = '密码太简单了，你怕是个傻子哦'return render(request,'reg.html',locals())

<h1>注册页面</h1>
<form action="" method="post"><p>username:<input type="text" name="username"><span>{{ errors.username }}</span></p><p>password:<input type="password" name="password"><span>{{ errors.password }}</span></p><input type="submit"></form>

from app01 import models
from django import forms
from django.forms import widgets

class MyForm(forms.Form):name = forms.CharField(max_length=6,label='用户名',error_messages={'max_length':'用户名最长6位','required':'用户名不能为空'})password = forms.CharField(max_length=8,min_length=3,error_messages={'max_length': '密码最长8位','required': '密码不能为空','min_length':'密码最少3位'},widget=widgets.PasswordInput(attrs={'class':'c1 form-control'}))confirm_password = forms.CharField(max_length=8, min_length=3, error_messages={'max_length': '确认密码最长8位','required': '确认密码不能为空','min_length': '确认密码最少3位'},widget=widgets.PasswordInput())email = forms.EmailField(error_messages={'invalid':'邮箱格式不正确','required':'邮箱不能为空'})gender = forms.ChoiceField(choices=((1, "男"), (2, "女"), (3, "保密")),label="性别",initial=3,  # 默认值widget=forms.widgets.RadioSelect())hobby = forms.ChoiceField(choices=((1, "篮球"), (2, "足球"), (3, "双色球"),),label="爱好",initial=3,widget=forms.widgets.Select())hobby1 = forms.MultipleChoiceField(choices=((1, "篮球"), (2, "足球"), (3, "双色球"),),label="爱好",initial=[1, 3],widget=forms.widgets.SelectMultiple())keep = forms.ChoiceField(label="是否记住密码",initial="checked",widget=forms.widgets.CheckboxInput())# 钩子函数# 局部钩子函数  （单个字段的校验利用局部钩子函数）def clean_name(self):name = self.cleaned_data.get('name')if '666' in name:self.add_error('name','光喊666是不行的，要有真实力!')return name  # return还是要加上的，兼容性考虑# 全局钩子函数  （多个字段的校验利用全局钩子函数）def clean(self):password = self.cleaned_data.get('password')confirm_password = self.cleaned_data.get('confirm_password')if not password == confirm_password:self.add_error('confirm_password',"两次密码不一致，你这个dsb!")return self.cleaned_datadef reg(request):# 生成一个空对象form_obj = MyForm()if request.method == 'POST':print(request.POST)form_obj = MyForm(request.POST)if form_obj.is_valid():print(form_obj.cleaned_data)models.User.objects.create(**form_obj.cleaned_data)return render(request,'reg.html',locals())

class User(models.Model):name = models.CharField(max_length=32)password = models.CharField(max_length=32)email = models.EmailField()

<h1>第一种渲染方式(可扩展性较差)</h1>
{{ form_obj.as_p }}
{{ form_obj.as_ul }}

<h1>第二种渲染方式</h1>
<form action=""><p>{{ form_obj.name.label }}{{ form_obj.name }}</p><p>{{ form_obj.password.label }}{{ form_obj.password }}</p><p>{{ form_obj.email.label }}{{ form_obj.email }}</p><input type="submit">
</form>

<h1>第三种渲染标签的方式</h1>
<form action="" method="post" novalidate>{% for foo in form_obj %}<p>{{ foo.label }}{{ foo }}</p><span>{{ foo.errors.0 }}</span>{% endfor %}<input type="submit">
</form></body>
</html>

def login(request):if request.method == 'POST':username = request.POST.get('username')password = request.POST.get('password')if username == 'khan' and password == '123':old_path = request.GET.get('next')if old_path:obj = redirect(old_path)else:obj = redirect('/home/')# 用户登录成功 朝浏览器设置一个cookie# obj.set_cookie('name','khan',expires=7*24*3600)obj.set_cookie('name','khan',max_age=5)return objreturn render(request,'login.html')from functools import wraps
def login_auth(func):@wraps(func)def inner(request,*args,**kwargs):# 校验cookie# print(request.get_full_path())old_path = request.get_full_path()if request.COOKIES.get('name'):return func(request,*args,**kwargs)return redirect('/login/?next=%s'%old_path)return inner@login_auth
def index(request):# # print(request.COOKIES.get('name'))# if request.COOKIES.get('name'):return HttpResponse('我是index页面，只有登录了才能看')@login_auth
def home(request):return HttpResponse('我是home页面，只有登录了才能看')@login_auth
def xxx(request):return HttpResponse('我是xxx页面，只有登录了才能看')def set_session(request):request.session['name'] = 'khan'request.session['name1'] = 'egon'request.session['name2'] = 'tank'request.session['name3'] = 'nick'request.session['name4'] = 'sean'return HttpResponse('ok')def get_session(request):print(request.session.get('name'))print(request.session.get('name1'))print(request.session.get('name2'))print(request.session.get('name3'))print(request.session.get('name4'))return HttpResponse('ok')def delete_session(request):request.session.delete()return HttpResponse('ok')def flush_session(request):request.session.flush()return HttpResponse('ok')

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title><script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script><link rel="stylesheet" href="/static/bootstrap-3.3.7/css/bootstrap.min.css"><script src="/static/bootstrap-3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<form action="" method="post"><p>username:<input type="text" name="username"></p><p>password:<input type="text" name="password"></p><input type="submit">
</form>
</body>
</html>