要说ModelForm，那就先说Form吧！
先给出一个Form示例：
models.py
from django.db import models
class UserType(models.Model):
caption=models.CharField(max_length=32)
class UserGroup(models.Model):
name=models.CharField(max_length=32)
class UserInfo(models.Model):
username=models.CharField(verbose_name="用户",max_length=32)
email=models.EmailField()
user_type=models.ForeignKey(to=‘UserType‘,to_field="id",on_delete=models.CASCADE) #关联UserType 一对一
u2g=models.ManyToManyField(UserGroup) #关联UserGroup 多对多
views.py
from django.shortcuts import render
from django import forms
from django.forms import fields
from app_01 import models
class UserInfoForm(forms.Form):
username = fields.CharField(max_length=32)
email = fields.EmailField()
user_type = fields.ChoiceField(
choices=models.UserType.objects.values_list("id","caption") #在页面上 把用户类型作为列表列上来了
)
def __init__(self,*args,**kwargs): #自动更新操作
super(UserInfoForm,self).__init__(*args,**kwargs)
self.fields[‘user_type‘].choices=models.UserType.objects.values_list("id","caption")
def index(request):
if request.method=="GET":
obj=UserInfoForm()
return render(request,"index.html",{‘obj‘:obj})
elif request.method=="POST":
obj=UserInfoForm(request.POST)
if obj.is_valid() :
obj.save() #验证成功 把所有的正确信息保存在数据库中
return render(request,‘index.html‘,{‘obj‘:obj})
index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="/index/" method="post">
{{ obj.as_p}}
{% csrf_token %}
<input type="submit" value="提交" />
</form>
</body>
</html>
在html上显示的效果为：
看了上面的示例，觉不觉得特麻烦？那让我们现在用ModelForm来实现吧！
其他不用改，只改views.py文件
from django.shortcuts import render
from django import forms
from django.forms import fields
from app_01 import models
class UserInfoModelForm(forms.ModelForm):
class Meta:
model=models.UserInfo
fields="__all__" #代指所有的字段
# models.UserInfo.objects.create(**obj.cleaned_data) #在数据库中自动进行创建 # models.UserInfo.objects.filter(id=1).update(**obj.cleaned_data) #在数据库中自动进行更新
def index(request):
if request.method=="GET":
obj=UserInfoModelForm()
return render(request,"index.html",{‘obj‘:obj})
elif request.method=="POST":
obj=UserInfoModelForm(request.POST)
if obj.is_valid() :
obj.save() #验证成功 把所有的正确信息保存在数据库中
return render(request,‘index.html‘,{‘obj‘:obj})
可以看到Form和ModelForm的区别了吧！
但是ModelForm也有弊端的，只能用它写小一点的程序，而大程序利用这个则不适用！
利用ModelForm来实践下吧！
Models.py
from django.db import models
class UserType(models.Model):
caption=models.CharField(max_length=32)
class UserGroup(models.Model):
name=models.CharField(max_length=32)
class UserInfo(models.Model):
username=models.CharField(verbose_name="用户",max_length=32)
email=models.EmailField()
user_type=models.ForeignKey(to=‘UserType‘,to_field="id",on_delete=models.CASCADE)
u2g=models.ManyToManyField(UserGroup)
Views.py
def user_list(request):
li=models.UserInfo.objects.all().select_related(‘user_type‘) #可以拿到UserInfo表内的数据，也可以拿到UserType表内的数据
return render(request,‘user_list.html‘,{‘li‘:li})
def user_edit(request,nid):
if request.method=="GET":
user_obj=models.UserInfo.objects.filter(id=nid).first()
mf=UserInfoModelForm(instance=user_obj) #这里不能瞎传 必须得有参数 instance 若无instance 则是在数据库内创建了一条数据，而不是直接对数据进行更改
return render(request,‘user_edit.html‘,{‘mf‘:mf ,‘nid‘:nid})
elif request.method=="POST":
user_obj = models.UserInfo.objects.filter(id=nid).first()
mf = UserInfoModelForm(request.POST,instance=user_obj)
if mf.is_valid(): #正确信息全部拿到
mf.save() #保存至数据库里
else:
print(mf.errors.as_json())
return render(request, ‘user_edit.html‘, {‘mf‘: mf, ‘nid‘: nid})
user_list.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<ul>
{% for row in li %}
<li>{{ row.username }}-{{ row.user_type.caption }}-<a href="/edit-{{ row.id }}/">编辑</a> </li>
{% endfor %}
</ul>
</body>
</html>
user_edit.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="/edit-{{ nid }}/" method="post">
{% csrf_token %}
{{ mf.as_p }}
<input type="submit" value="提交" />
</form>
</body>
</html>
urls.py
from django.contrib import admin
from django.urls import path
from app_01 import views
from django.conf.urls import url
import re
urlpatterns = [
path(‘admin/‘, admin.site.urls),
path(‘index/‘, views.index),
path(‘user_list/‘, views.user_list),
url(r‘^edit-(\d+)/‘, views.user_edit) #正则表达式
]
user_list上的操作效果为：
user_erit上的操作效果为
原文地址：https://www.cnblogs.com/zhuifeng-mayi/p/9129345.html
时间： 2024-10-24 04:21:09