form
组件组要功能：
- 生成HTML标签
- 验证用户数据（显示错误信息）
- HTML Form提交保留上次提交数据
- 初始化页面显示内容
1.创建Form类时，主要涉及到 【字段】 和 【插件】，字段用于对用户请求数据的验证，插件用于自动生成HTML;
① Django内置字段如下：
Field
required=True, 是否允许为空
widget=None, HTML插件
label=None, 用于生成Label标签或显示内容
initial=None, 初始值
help_text='', 帮助信息(在标签旁边显示)
error_messages=None, 错误信息 {'required': '不能为空', 'invalid': '格式错误'}
show_hidden_initial=False, 是否在当前插件后面再加一个隐藏的且具有默认值的插件（可用于检验两次输入是否一直）
validators=[], 自定义验证规则
localize=False, 是否支持本地化
disabled=False, 是否可以编辑
label_suffix=None Label内容后缀
CharField(Field)
max_length=None, 最大长度
min_length=None, 最小长度
strip=True 是否移除用户输入空白
IntegerField(Field)
max_value=None, 最大值
min_value=None, 最小值
FloatField(IntegerField)
...
DecimalField(IntegerField)
max_value=None, 最大值
min_value=None, 最小值
max_digits=None, 总长度
decimal_places=None, 小数位长度
BaseTemporalField(Field)
input_formats=None 时间格式化
DateField(BaseTemporalField) 格式：2015-09-01
TimeField(BaseTemporalField) 格式：11:12
DateTimeField(BaseTemporalField)格式：2015-09-01 11:12
DurationField(Field) 时间间隔：%d %H:%M:%S.%f
...
RegexField(CharField)
regex, 自定制正则表达式
max_length=None, 最大长度
min_length=None, 最小长度
error_message=None, 忽略，错误信息使用 error_messages={'invalid': '...'}
EmailField(CharField)
...
FileField(Field)
allow_empty_file=False 是否允许空文件
ImageField(FileField)
...
注：需要PIL模块，pip3 install Pillow
以上两个字典使用时，需要注意两点：
- form表单中 enctype="multipart/form-data"
- view函数中 obj = MyForm(request.POST, request.FILES)
URLField(Field)
...
BooleanField(Field)
...
NullBooleanField(BooleanField)
...
ChoiceField(Field)
...
choices=(), 选项，如：choices = ((0,'上海'),(1,'北京'),)
required=True, 是否必填
widget=None, 插件，默认select插件
label=None, Label内容
initial=None, 初始值
help_text='', 帮助提示
ModelChoiceField(ChoiceField)
... django.forms.models.ModelChoiceField
queryset, # 查询数据库中的数据
empty_label="---------", # 默认空显示内容
to_field_name=None, # HTML中value的值对应的字段
limit_choices_to=None # ModelForm中对queryset二次筛选
ModelMultipleChoiceField(ModelChoiceField)
... django.forms.models.ModelMultipleChoiceField
TypedChoiceField(ChoiceField)
coerce = lambda val: val 对选中的值进行一次转换
empty_value= '' 空值的默认值
MultipleChoiceField(ChoiceField)
...
TypedMultipleChoiceField(MultipleChoiceField)
coerce = lambda val: val 对选中的每一个值进行一次转换
empty_value= '' 空值的默认值
ComboField(Field)
fields=() 使用多个验证，如下：即验证最大长度20，又验证邮箱格式
fields.ComboField(fields=[fields.CharField(max_length=20), fields.EmailField(),])
MultiValueField(Field)
PS: 抽象类，子类中可以实现聚合多个字典去匹配一个值，要配合MultiWidget使用
SplitDateTimeField(MultiValueField)
input_date_formats=None, 格式列表：['%Y--%m--%d', '%m%d/%Y', '%m/%d/%y']
input_time_formats=None 格式列表：['%H:%M:%S', '%H:%M:%S.%f', '%H:%M']
FilePathField(ChoiceField) 文件选项，目录下文件显示在页面中
path, 文件夹路径
match=None, 正则匹配
recursive=False, 递归下面的文件夹
allow_files=True, 允许文件
allow_folders=False, 允许文件夹
required=True,
widget=None,
label=None,
initial=None,
help_text=''
GenericIPAddressField
protocol='both', both,ipv4,ipv6支持的IP格式
unpack_ipv4=False 解析ipv4地址，如果是::ffff:192.0.2.1时候，可解析为192.0.2.1， PS：protocol必须为both才能启用
SlugField(CharField) 数字，字母，下划线，减号（连字符）
...
UUIDField(CharField) uuid类型
...
- 常用字段(重点）
ChoiceField ***** MultipleChoiceField CharField IntegerField DecimalField DateField DateTimeField EmailField GenericIPAddressField FileField RegexField
② Django内置插件：
TextInput(Input) NumberInput(TextInput) EmailInput(TextInput) URLInput(TextInput) PasswordInput(TextInput) HiddenInput(TextInput) Textarea(Widget) DateInput(DateTimeBaseInput) DateTimeInput(DateTimeBaseInput) TimeInput(DateTimeBaseInput) CheckboxInput Select NullBooleanSelect SelectMultiple RadioSelect CheckboxSelectMultiple FileInput ClearableFileInput MultipleHiddenInput SplitDateTimeWidget SplitHiddenDateTimeWidget SelectDateWidget
常用选择插件
# 单radio，值为字符串 # user = fields.CharField( # initial=2, # widget=widgets.RadioSelect(choices=((1,'上海'),(2,'北京'),)) # ) # 单radio，值为字符串 # user = fields.ChoiceField( # choices=((1, '上海'), (2, '北京'),), # initial=2, # widget=widgets.RadioSelect # ) # 单select，值为字符串 # user = fields.CharField( # initial=2, # widget=widgets.Select(choices=((1,'上海'),(2,'北京'),)) # ) # 单select，值为字符串 # user = fields.ChoiceField( # choices=((1, '上海'), (2, '北京'),), # initial=2, # widget=widgets.Select # ) # 多选select，值为列表 # user = fields.MultipleChoiceField( # choices=((1,'上海'),(2,'北京'),), # initial=[1,], # widget=widgets.SelectMultiple # ) # 单checkbox # user = fields.CharField( # widget=widgets.CheckboxInput() # ) # 多选checkbox,值为列表 # user = fields.MultipleChoiceField( # initial=[2, ], # choices=((1, '上海'), (2, '北京'),), # widget=widgets.CheckboxSelectMultiple # )
2.表单验证
from django.conf.urls import url from django.contrib import admin from app01 import views from app02 import views as v2 urlpatterns = [ url(r'^f1.html$', v2.f1), ]
from django.shortcuts import render,HttpResponse,redirect from django import forms from django.forms import fields class F1From(forms.Form): user = fields.CharField( max_length=18,min_length=6,required=True, error_messages={ 'required': '用户不能为空', 'max_length': '太长了', 'min_length': '太短了', 'invalid': '格式不正确',#格式不正确都是invalid } ) pwd = fields.CharField( min_length=6, required=True, error_messages={ 'required' : '密码不能为空', 'min_length': '太短了', 'invalid' : '密码格式不正确', } ) email = fields.EmailField(required=True, error_messages={ 'required' : '邮箱不能为空' , 'invalid' : '格式需为邮箱格式', } ) age = fields.IntegerField( required=True, error_messages={ 'required': '年龄不能为空', 'invalid' : '年龄需为数字', } ) def f1(request): if request.method == "GET": obj = F1From() return render(request,'f1.html',{'obj':obj}) else: # u = request.POST.get('user') # p = request.POST.get('pwd') # e = request.POST.get('email') # a = request.POST.get('age') # 1.检查是否为空 # 2.检查格式是否正确 # print(u,p,e,a) obj = F1From(request.POST) # 是否全部验证成功 if obj.is_valid(): #用户提交的数据 print('验证成功',obj.cleaned_data) return redirect('http://www.baidu.com') # return render(request,'f1.html',{'obj':obj}) else: print('验证失败',obj.errors) return render(request,'f1.html',{'obj':obj})
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form id="fm" action="/f1.html" method="POST"> <P>用户: {{ obj.user }}{{ obj.errors.user.0 }}</P>{# 一个输入项可能包含多种格式错误，取第一个 .0 #} <P>密码: {{ obj.pwd }}{{ obj.errors.pwd.0 }}</P> <P>邮箱: {{ obj.email }}{{ obj.errors.email.0 }}</P> <P>年龄: {{ obj.age }}{{ obj.errors.age.0 }}</P> <input type="submit" value="form提交"/> </form> </body> </html>
效果展示：
3、初始化默认值——form表单简单更改单表数据库数据（增，改，查）
from django.conf.urls import url from django.contrib import admin from app01 import views urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^users/', views.users), url(r'^add_user/', views.add_user), url(r'^edit_user-(d+)/', views.edit_user), ]
from django.shortcuts import render,HttpResponse,redirect from app01 import models def users(request): user_list = models.UserInfo.objects.all() return render(request,'users.html',{'user_list':user_list}) from app01.forms import UserForm def add_user(request): if request.method == 'GET': obj = UserForm() return render(request,'add_user.html',{'obj':obj}) else: obj = UserForm(request.POST) if obj.is_valid(): print('验证成功',obj.cleaned_data) # models.UserInfo.objects.create( # username = obj.cleaned_data['username'], # email = obj.cleaned_data['email'], # ) # 后面一句可以直接代替上面语句 models.UserInfo.objects.create(**obj.cleaned_data) return redirect('/users/') else: print('验证失败',obj.errors) return render(request,'add_user.html',{'obj':obj}) def edit_user(request,nid): if request.method == 'GET': # p = request.GET.get('nid') data = models.UserInfo.objects.filter(id=nid).first() # 拿到一个对象 obj = UserForm({'username':data.username,'email':data.email}) return render(request,'edit.html',{'obj':obj,'nid':nid }) else: obj = UserForm(request.POST) if obj.is_valid(): models.UserInfo.objects.filter(id=nid).update(**obj.cleaned_data) return redirect('/users/') else: return render(request, 'edit.html', {'obj': obj, 'nid': nid})
# !/usr/bin/env python # -*- coding: utf-8 -*- # Author:daly from django import forms as dforms from django.forms import fields class UserForm(dforms.Form): username = fields.CharField( required=True, min_length=6, error_messages={ 'required':"用户不能为空", 'min_length':'太短了', } ) email = fields.EmailField( required=True, error_messages={ 'required': "邮箱不能为空", 'invalid':'邮箱格式错误', } )
from django.db import models # Create your models here. class UserInfo(models.Model): username = models.CharField(max_length=32) email = models.EmailField(max_length=32)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <a href="/add_user/">添加</a> <ul> {% for row in user_list %} <li>{{ row.id }}-{{ row.username }}-{{ row.email }}|<a href="/edit_user-{{ row.id }}">编辑</a></li> {% endfor %} </ul> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form method="post" action="/add_user/" novalidate> {% csrf_token %} <p>用户：{{ obj.username }}{{ obj.errors.username.0 }}</p> <p>邮箱：{{ obj.email }}{{ obj.errors.email.0 }}</p> <input type="submit" value="提交"/> </form> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/edit_user-{{ nid }}/" method="post" novalidate> {% csrf_token %} <p>用户：{{ obj.username }}{{ obj.errors.username.0 }}</p> <p>邮箱：{{ obj.email }}{{ obj.errors.email.0 }}</p> <input type="submit" value="提交"/> </form> </body> </html>
效果展示：
4.动态更新实时数据
在使用选择标签时，需要注意choices的选项可以从数据库中获取，但是由于是静态字段（类变量） ***获取的值无法实时更新***，那么需要自定义构造方法从而达到此目的。
方法一：(推荐)
from django.conf.urls import url from django.contrib import admin from app01 import views from app02 import views as v2 urlpatterns = [ url(r'^love/', v2.love), ]
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>非诚勿扰</h1> <P>价格：{{ obj.prive }}</P> <P>人员：{{ obj.user_id }}</P> </body> </html>
from django.db import models # Create your models here. class UserInfo(models.Model): username = models.CharField(max_length=32) email = models.EmailField(max_length=32)
from django.shortcuts import render from django import forms from django.forms import fields from django.forms import widgets from app01 import models class LoveForm(forms.Form): user_id = fields.IntegerField( widget=widgets.Select( # choices=[(0,'苹果'),(1,'梨子'),(2,'香蕉')], #自己创建 # choices= models.UserInfo.objects.values_list('id','username') #也可以从数据库取数据 ) ) prive = fields.IntegerField() def __init__(self,*args,**kwargs): #拷贝所有静态字段，复制给self.fields (顺序：super->self.fields) super(LoveForm,self).__init__(*args,**kwargs) self.fields['user_id'].widget.choices = models.UserInfo.objects.values_list('id','username') def love(requset): obj = LoveForm() return render(requset,'love.html',{'obj':obj})
效果展示：
方法二：(依赖于model中的__str__方法，多个slecte框不适用，耦合性太强)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>非诚勿扰</h1> <P>价格：{{ obj.prive }}</P> <P>人员：{{ obj.user_id }}</P> <P>人员：{{ obj.user_id2 }}</P> <!--新增--> </body> </html>
from django.db import models # Create your models here. class UserInfo(models.Model): username = models.CharField(max_length=32) email = models.EmailField(max_length=32) def __str__(self): #新增 return self.username #新增
from django.shortcuts import render from django import forms from django.forms import fields from django.forms import widgets from app01 import models class LoveForm(forms.Form): user_id = fields.IntegerField( widget=widgets.Select( # choices=[(0,'苹果'),(1,'梨子'),(2,'香蕉')], #自己创建 # choices= models.UserInfo.objects.values_list('id','username') #也可以从数据库取数据 ) ) prive = fields.IntegerField() from django.forms.models import ModelChoiceField #新增 user_id2 =ModelChoiceField( #新增 queryset=models.UserInfo.objects.all(), #新增 to_field_name='id', #新增 ) #新增 def __init__(self,*args,**kwargs): #拷贝所有静态字段，复制给self.fields (顺序：super->self.fields) super(LoveForm,self).__init__(*args,**kwargs) self.fields['user_id'].widget.choices = models.UserInfo.objects.values_list('id','username') def love(requset): obj = LoveForm() return render(requset,'love.html',{'obj':obj})
效果展示：
5.Ajax提交验证（验证；无需上次内容）
- 返回HttpResponse
- 前端：跳转或错误信息
如果想要ajax提交数据到django后台，对页面进行跳转，需要在ajax 中验证后进行跳转，在后台进行跳转不生效.
from django.conf.urls import url from django.contrib import admin from app01 import views from app02 import views as v2 urlpatterns = [ url(r'^ajax/', v2.ajax), ]
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form id="fm" action="/ajax/" method="post" novalidate> {% csrf_token %} {{ obj.as_p }} <input type="button" value="ajax提交" id="btn"/> </form> <script src="/static/jquery-3.1.1.js/"></script> <script> $(function () { $('#btn').click(function () { $.ajax({ url:'/ajax/', type:'POST', data:$('#fm').serialize(), dataType:'JSON', success:function (arg) { //arg:状态，错误信息 if (arg.status == '钱'){ window.location.href="http://www.baidu.com" } console.log(arg); } }) }) }) </script> </body> </html>
class AjaxForm(forms.Form): prive = fields.IntegerField() user_id = fields.IntegerField( widget=widgets.Select( choices=[(0,'苹果'),(1,'梨子'),(2,'香蕉')], ) ) def ajax(request): if request.method == 'GET': obj = AjaxForm() return render(request,'ajax.html',{'obj':obj}) else: ret = {'status':'没钱','message':None} import json obj = AjaxForm(request.POST) # print(obj.cleaned_data) if obj.is_valid(): print(obj.cleaned_data) # return redirect('http://www.baidu.com') ret['status']='钱' return HttpResponse(json.dumps(ret)) else: print(type(obj.errors)) from django.forms.utils import ErrorDict print(obj.errors.as_ul()) print(obj.errors.as_json()) print(obj.errors.as_data()) ret['message']= obj.errors return HttpResponse(json.dumps(ret))
自定义验证规则(from组件扩展)
方式一：
from django.forms import Form
from django.forms import widgets
from django.forms import fields
from django.core.validators import RegexValidator
class MyForm(Form):
user = fields.CharField(
validators=[RegexValidator(r'^[0-9]+$', '请输入数字'), RegexValidator(r'^159[0-9]+$', '数字必须以159开头')],
)
方式二：
from django.forms import Form
from django.forms import widgets
from django.forms import fields
from django.core.validators import RegexValidator
class MyForm(Form):
user = fields.RegexField(r'^[0-9]+$',error_messages={'invalid': '格式错误'})
基于源码流程
a. 单字段（clean_field）
from django.core.exceptions import NON_FIELD_ERRORS, ValidationError
class AjaxForm(forms.Form):
username = fields.CharField()
user_id = fields.IntegerField(
widget=widgets.Select(choices=[(0,'alex'),(1,'刘皓宸'),(2,'杨建'),])
)
# 自定义方法 clean_字段名
# 必须返回值self.cleaned_data['username']
# 如果出错：raise ValidationError('用户名已存在')
def clean_username(self):
v = self.cleaned_data['username']
if models.UserInfo.objects.filter(username=v).count():
# 整体错了
# 自己详细错误信息
raise ValidationError('用户名已存在')
return v
def clean_user_id(self):
return self.cleaned_data['user_id']
b. 整体错误验证（clean_form）
class AjaxForm(forms.Form):
username = fields.CharField()
user_id = fields.IntegerField(
widget=widgets.Select(choices=[(0,'alex'),(1,'刘皓宸'),(2,'杨建'),])
)
# 自定义方法 clean_字段名
# 必须返回值self.cleaned_data['username']
# 如果出错：raise ValidationError('用户名已存在')
def clean_username(self):
v = self.cleaned_data['username']
if models.UserInfo.objects.filter(username=v).count():
# 整体错了
# 自己详细错误信息
raise ValidationError('用户名已存在')
return v
def clean_user_id(self):
return self.cleaned_data['user_id']
def clean(self):
value_dict = self.cleaned_data
v1 = value_dict.get('username')
v2 = value_dict.get('user_id')
if v1 == 'root' and v2==1:
raise ValidationError('整体错误信息')
return self.cleaned_data