django中的散碎知识

models之ManytoMany自关联

from django.shortcuts import render,HttpResponse,redirect
from app01 import models
# Create your views here.
def test(request):
    # models.UserInfo.objects.create(username='zhangsan',password='123',name='张三',gender='1')
    # models.UserInfo.objects.create(username='lisi',password='123',name='李四',gender='1')
    # models.UserInfo.objects.create(username='wangwu',password='123',name='王五',gender='1')
    # models.UserInfo.objects.create(username='xiaohong',password='123',name='小红',gender='2')
    # models.UserInfo.objects.create(username='xiaobai',password='123',name='小白',gender='2')
    # models.UserInfo.objects.create(username='xiaolan',password='123',name='小兰',gender='2')

    # zhangsan=models.UserInfo.objects.filter(id=1).first()
    # # print(zhangsan)
    # result=zhangsan.girls.all()
    # print(result)
    # for i in result:
    #     print(i.g.name)




    zhangsan=models.UserInfo.objects.filter(id=1).first()
    v=zhangsan.m.all()
    print(v)
    xiaobai=models.UserInfo.objects.filter(id=5).first()
    result=xiaobai.userinfo_set.all()
    print(result)
    return HttpResponse('ssss')

from django.db import models

# Create your models here.
class UserInfo(models.Model):
    name=models.CharField(max_length=32)
    username=models.CharField(max_length=32)
    password=models.CharField(max_length=32)
    gender_choice=(
        (1,'男'),
        (2,'女'),
    )
    gender=models.IntegerField(choices=gender_choice)
    m = models.ManyToManyField('UserInfo')
# class U2U(models.Model):
#     b=models.ForeignKey('UserInfo',on_delete=models.PROTECT,related_name='girls')
#     g=models.ForeignKey('UserInfo',on_delete=models.PROTECT,related_name='boys')

ORM中queryset对象之后返回数据类型：

1. values返回是字典列表;
2. values_list返回的是元组列表，

3. values_list加上

   flat=True之后返回值列表

4. .first可以取queryset对象

view.py利用装饰器对页面做session验证：

from functools import wraps
def check_login(f):
    @wraps(f)
    def inner(request):
        if request.session.get('is_login'):
            return f(request)
        else:
            return redirect('/login.html/')
    return inner