Django中Form的基本使用
from django import forms
from django.forms import fields
class UserInfo(forms.Form):
username = fields.CharField(required=True,error_messages={
'required':'username不能为空'
}) # 正则表达式
password = fields.CharField(required=True,error_messages={
'required':'password不能为空'
})
email = fields.EmailField(required=True,error_messages={
'required':'email不能为空',
'invalid':'email格式错误'
}) #不能为空
# 获取用户提交的数据 request.POST
# 数据和正则表达式进行验证
# 1.是否验证成功
# 2.成功：获取数据
# 3.失败：显示错误信息
def add_user(request):
if request.method == 'GET':
return render(request,'add_user.html')
else:
obj = UserInfo(request.POST) # 定义一个form实例
# 获取是否验证成功 使用is_valid方法
if obj.is_valid():
print('验证通过',obj.cleaned_data)
models.UserInfo.objects.create(**obj.cleaned_data)
else:
print('错误信息',obj.errors)
总结：
Form验证：
a.Form类
b. obj = Form()
obj.username <input .../>
c. obj = Form(request.POST)
obj.username <input value=..../>
d. 验证
if obj.is_valid()
print('数据信息',obj.cleaned_data)
models.UserInfo.objects.create(**obj.cleaned_data)
else:
print('错误信息',obj.errors)
print('错误信息',obj.errors.usernaem[0])
return render(request,'add_user/',{'obj':obj})
===============>
Form 生成HTML标签
在index中添加 {{ obj.usernaem }} 自动生成html标签
from django.forms import widgets
widget=widgets.TextInput(attr={'class':'xxxx'}) #设置标签类型
Form 编辑
#============urls.py================
from app01 import views
urlpatterns = [
url(r'edit_user/(?P<uid>\d+)',views.edit_user),
]
#============views.py================
from django import forms
from django.forms import fields
from django.forms import widgets
class UserForm(forms.Form):
username = fields.CharField(
required=True,
error_messages = {'required':'username不能为空'},
widget = widgets.TextInput(attrs={'class':'form-control','placeholder':'用户名'}),
)
password = fields.CharField(
required = True,
error_messages = {'required':'password不能为空'},
widget = widgets.TextInput(attrs={'class':'form-control','placeholder':'密码'}),
)
email = fields.CharField(
required = True,
error_messages = {'required':'email不能为空'},
widget = widgets.TextInput(attrs={'class':'form-control','placeholder':'邮件'}),
)
from app01 import models
def edit_user(request,uid):
if request.method == 'GET':
user_obj = models.UserInfo.objects.filter(id=uid).first()
obj = UserForm(initial={'username':user_obj.username,'password':user_obj.password,'email':user_obj.email})
#或者
# user = models.UserInfo.objects.values('username','password','email').filter(id=uid).first()
# obj = UserForm(initial=user)
return render(request,'edit_user.html',{'obj':obj,'uid':uid})
elif request.method == 'POST':
obj = UserForm(request.POST)
if obj.is_valid():
models.UserInfo.objects.filter(id=uid).update(**obj.cleaned_data)
return redirect('/index1/')
else:
return render(request,'edit_user.html',{'obj':obj,'uid':uid})
Form中的select下拉框：
ut_id = fields.IntegerField(
required=True,
widget = widgets.Select(
attrs = {'class':'form-control'},
choices = [],
)
)
def __init__(self,*args,**kwargs)
super(UserForm,self).__init__(*args,**kwargs)
self.fields['ut_id'].widget.choices = models.UserType.values_list('id','usertype')
Form 小结：
1. 做提交数据的验证
2. 生成对应的HTML
3.
跨表操作时的数据库性能
select_related('Forkey')
