Django用自定义cookies 实现登录，注册，退出

#注册
def regist(req):
if req.method == 'POST':
uf = UserForm(req.POST)
if uf.is_valid():
#获得表单数据
username = uf.cleaned_data['username']
password = uf.cleaned_data['password']
#添加到数据库
User.objects.create(username= username,password=password)
return HttpResponse('regist success!!')
else:
uf = UserForm()
return render_to_response('regist.html',{'uf':uf}, context_instance=RequestContext(req))

#登陆
def login(req):
if req.method == 'POST':
uf = UserForm(req.POST)
if uf.is_valid():
#获取表单用户密码
username = uf.cleaned_data['username']
password = uf.cleaned_data['password']
#获取的表单数据与数据库进行比较
user = User.objects.filter(username__exact = username,password__exact = password)
if user:
#比较成功，跳转index
response = HttpResponseRedirect('/online/index/')
#将username写入浏览器cookie,失效时间为3600
response.set_cookie('username',username,3600)
return response
else:
#比较失败，还在login
return HttpResponseRedirect('/online/login/')
else:
uf = UserForm()
return render_to_response('login.html',{'uf':uf},context_instance=RequestContext(req))

#登陆成功
def index(req):
username = req.COOKIES.get('username','')
return render_to_response('index.html' ,{'username':username})

#退出
def logout(req):
response = HttpResponse('logout !!')
#清理cookie里保存username
response.delete_cookie('username')
return response