Django之Form
目录
一、说明
Django的Form主要具有一下几大功能：
- 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
二、参数说明
1、内置字段
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 ...
2、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
# 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 # )
三、自定义验证规则
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
import re from django.forms import Form from django.forms import widgets from django.forms import fields from django.core.exceptions import ValidationError # 自定义验证规则 def mobile_validate(value): mobile_re = re.compile(r'^(13[0-9]|15[012356789]|17[678]|18[0-9]|14[57])[0-9]{8}$') if not mobile_re.match(value): raise ValidationError('手机号码格式错误') class PublishForm(Form): title = fields.CharField(max_length=20, min_length=5, error_messages={'required': '标题不能为空', 'min_length': '标题最少为5个字符', 'max_length': '标题最多为20个字符'}, widget=widgets.TextInput(attrs={'class': "form-control", 'placeholder': '标题5-20个字符'})) # 使用自定义验证规则 phone = fields.CharField(validators=[mobile_validate, ], error_messages={'required': '手机不能为空'}, widget=widgets.TextInput(attrs={'class': "form-control", 'placeholder': u'手机号码'})) email = fields.EmailField(required=False, error_messages={'required': u'邮箱不能为空','invalid': u'邮箱格式错误'}, widget=widgets.TextInput(attrs={'class': "form-control", 'placeholder': u'邮箱'}))
方式三 clean_xxx，需要return该xxx字段的值
from django import forms from django.forms import fields from django.forms import widgets from django.core.exceptions import ValidationError from django.core.validators import RegexValidator class FInfo(forms.Form): username = fields.CharField(max_length=5, validators=[RegexValidator(r'^[0-9]+$', 'Enter a valid extension.', 'invalid')], ) email = fields.EmailField() def clean_username(self): """ Form中字段中定义的格式匹配完之后，执行此方法进行验证 :return: """ value = self.cleaned_data['username'] if "666" in value: raise ValidationError('666已经被玩烂了...', 'invalid') return value
方式四 clean，需return self.cleaned_data
class RegisterForm(Form): username = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control"})) email = fields.EmailField(widget=widgets.TextInput(attrs={"class":"form-control"})) password = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control","type":"password"})) password2 = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control","type":"password"})) avatar = fields.FileField(widget=widgets.FileInput(attrs={"class":"f1","id":"imgSelect"})) code = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control"})) nickname = fields.CharField(required=False,widget=widgets.TextInput(attrs={"class":"form-control"})) create_time = fields.DateTimeField(required=False) # 传入request是为了检查session中的code字段 def __init__(self,request,*args,**kwargs): # 传入request super(RegisterForm, self).__init__(*args,**kwargs) self.request = request def clean_code(self): input_code = self.cleaned_data["code"] session_code = self.request.session.get("code") if input_code.upper() != session_code.upper(): raise ValidationError("验证码错误") return input_code # 检出用户名是否已被占用 def clean_username(self): username = self.cleaned_data["username"] if models.UserInfo.objects.filter(username=username): raise ValidationError("该用户已被占用") return username # 检出邮箱是否已被占用 def clean_email(self): email = self.cleaned_data["email"] if models.UserInfo.objects.filter(email=email): raise ValidationError("该邮箱已被占用") return email # 检出nickname是否已被占用 def clean_nickname(self): nickname = self.cleaned_data["nickname"] if models.UserInfo.objects.filter(nickname=nickname): raise ValidationError("该昵称已被占用") return nickname def clean(self): # 检查两次密码是否一致 p1 = self.cleaned_data.get("password") p2 = self.cleaned_data.get("password2") if p1 != p2: self.add_error("password2", ValidationError("密码不一致")) # raise ValidationError("密码不一致") else: self.cleaned_data.pop("password2",None) # 如果一致，则去除password2，只保留password，为了与数据库字段一致（数据库只有password） # return self.cleaned_data # return None # 两者均可 # 如无创建时间，添加创建时间 # if not self.cleaned_data.get("create_time"): # self.cleaned_data["create_time"] = time.strftime("%Y-%m-%d") # 如无nickname，添加nickname if not self.cleaned_data.get("nickname"): self.cleaned_data["nickname"] = self.cleaned_data.get("username","")+str(int(time.time())) # 如果验证码正确，去除code，目的是与数据库字段一致（数据库没code） if self.cleaned_data.get("code"): self.cleaned_data.pop("code") return self.cleaned_data
方式五 同时生成多个标签进行验证
from django.forms import Form from django.forms import widgets from django.forms import fields from django.core.validators import RegexValidator ############## 自定义字段 ############## class PhoneField(fields.MultiValueField): def __init__(self, *args, **kwargs): # Define one message for all fields. error_messages = { 'incomplete': 'Enter a country calling code and a phone number.', } # Or define a different message for each field. f = ( fields.CharField( error_messages={'incomplete': 'Enter a country calling code.'}, validators=[ RegexValidator(r'^[0-9]+$', 'Enter a valid country calling code.'), ], ), fields.CharField( error_messages={'incomplete': 'Enter a phone number.'}, validators=[RegexValidator(r'^[0-9]+$', 'Enter a valid phone number.')], ), fields.CharField( validators=[RegexValidator(r'^[0-9]+$', 'Enter a valid extension.')], required=False, ), ) super(PhoneField, self).__init__(error_messages=error_messages, fields=f, require_all_fields=False, *args, **kwargs) def compress(self, data_list): """ 当用户验证都通过后，该值返回给用户 :param data_list: :return: """ return data_list ############## 自定义插件 ############## class SplitPhoneWidget(widgets.MultiWidget): def __init__(self): ws = ( widgets.TextInput(), widgets.TextInput(), widgets.TextInput(), ) super(SplitPhoneWidget, self).__init__(ws) def decompress(self, value): """ 处理初始值，当初始值initial不是列表时，调用该方法 :param value: :return: """ if value: return value.split(',') return [None, None, None]
四、实例
1、简单实例
from django.contrib import admin from django.urls import path,re_path from app01 import views urlpatterns = [ path('admin/', admin.site.urls), re_path("^$",views.index) ]
from django.db import models class User(models.Model): user = models.CharField(max_length=64) gender_choice = ( (1,"男"), (2,"女"), ) gender = models.IntegerField(choices=gender_choice) city_choice = ( (1,"上海"), (2,"北京") ) city = models.IntegerField(choices=city_choice) pwd = models.CharField(max_length=64)
from django.shortcuts import render, redirect from .forms import MyForm def index(request): if request.method == "GET": obj = MyForm() return render(request, 'index.html', {'form': obj}) elif request.method == "POST": obj = MyForm(request.POST, request.FILES) if obj.is_valid(): values = obj.clean() print(values) else: errors = obj.errors print(errors) return render(request, 'index.html', {'form': obj}) else: return redirect('http://www.google.com')
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/" method="POST" enctype="multipart/form-data"> <p>{{ form.user }} {{ form.user.errors }}</p> <p>{{ form.gender }} {{ form.gender.errors }}</p> <p>{{ form.city }} {{ form.city.errors }}</p> <p>{{ form.pwd }} {{ form.pwd.errors }}</p> <input type="submit"/> </form> </body> </html>
from django.forms import Form from django.forms import widgets from django.forms import fields class MyForm(Form): user = fields.CharField( widget=widgets.TextInput(attrs={'id': 'i1', 'class': 'c1'}) ) gender = fields.ChoiceField( choices=((1, '男'), (2, '女'),), initial=2, widget=widgets.RadioSelect ) city = fields.CharField( initial=2, widget=widgets.Select(choices=((1, '上海'), (2, '北京'),)) ) pwd = fields.CharField( widget=widgets.PasswordInput(attrs={'class': 'c1'}, render_value=True) )
另，其他参数
<form method="POST" enctype="multipart/form-data"> {% csrf_token %} <p>label:{{ form.user.label }}</p> <p>id_for_label:{{ form.user.id_for_label }}</p> <p>label_tag:{{ form.user.label_tag }}</p> <p>errors:{{ form.user.errors }}</p> <p>{{ form.user }} {{ form.user.errors }}</p> <input type="submit" /> </form>
2、为初始页面添加初始值
from django.shortcuts import render,redirect from app01 import models from django.forms import Form from django.forms import fields from django.forms import widgets from django.forms import models as form_model class TestForm(Form): user = fields.CharField() email = fields.EmailField() ug_id = fields.ChoiceField( widget=widgets.Select, choices=[] ) m2m_id = form_model.ModelMultipleChoiceField( widget=widgets.SelectMultiple, queryset = models.Role.objects.all() ) def __init__(self,*args,**kwargs): super(TestForm, self).__init__(*args,**kwargs) self.fields["ug_id"].choices = models.UserGroup.objects.values_list("id","title") # 实时刷新 # self.fields["m2m_id"].choices = models.Role.objects.values_list("id","name") def test(request): if request.method == "GET": val = { "user":"root", # "email":"root@qq.com", # 隐去，则会说required "ug_id":"1", "m2m_id":["1","2",] } form = TestForm(val) context = { "form":form, } return render(request,"test.html",context) else: form = TestForm(request.POST) if form.is_valid(): # print(form.cleaned_data) models.UserInfo.objects.create(**form.cleaned_data) return redirect("http://www.baidu.com") context = { "form":form, } return render(request,"test.html",context)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>test页面</h1> <form method="POST" > {% csrf_token %} {# {{ form.as_p }}#} <p>name:{{ form.user }}{{ form.user.errors.0 }}</p> <p>email:{{ form.email }}{{ form.email.errors.0 }}</p> <p>ug:{{ form.ug_id }}{{ form.ug_id.errors.0 }}</p> <p>m2m:{{ form.m2m_id }}{{ form.m2m_id.errors.0 }}</p> <input type="submit"> </form> </body> </html>
3、动态生成choices对应的标签
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 ***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、自定义构造方法
from django.shortcuts import render,redirect from app01 import models from django.forms import Form from django.forms import fields from django.forms import widgets from django.forms import models as form_model class TestForm(Form): user = fields.CharField() email = fields.EmailField() ug_id = fields.ChoiceField( widget=widgets.Select, choices=[] ) m2m_id = fields.ChoiceField( widget=widgets.SelectMultiple, choices=[] ) def __init__(self,*args,**kwargs): super(TestForm, self).__init__(*args,**kwargs) self.fields["ug_id"].choices = models.UserGroup.objects.values_list("id","title") # 实时刷新 self.fields["m2m_id"].choices = models.Role.objects.values_list("id","name") def test(request): if request.method == "GET": form = TestForm() context = { "form":form, } return render(request,"test.html",context) else: form = TestForm(request.POST) if form.is_valid(): # print(form.cleaned_data) models.UserInfo.objects.create(**form.cleaned_data) return redirect("http://www.baidu.com") context = { "form":form, } return render(request,"test.html",context)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>test页面</h1> <form method="POST" > {% csrf_token %} {# {{ form.as_p }}#} <p>name:{{ form.user }}{{ form.user.errors.0 }}</p> <p>email:{{ form.email }}{{ form.email.errors.0 }}</p> <p>ug:{{ form.ug_id }}{{ form.ug_id.errors.0 }}</p> <p>m2m:{{ form.m2m_id }}{{ form.m2m_id.errors.0 }}</p> <input type="submit"> </form> </body> </html>
方法二、使用django提供的ModelChoiceField和ModelMultipleChoiceField字段来实现
from django.shortcuts import render,redirect from app01 import models from django.forms import Form from django.forms import fields from django.forms import widgets from django.forms.models import ModelMultipleChoiceField,ModelChoiceField class TestForm(Form): user = fields.CharField() email = fields.EmailField() ug_id = ModelChoiceField( queryset=models.UserGroup.objects.all() ) m2m_id = ModelMultipleChoiceField( queryset = models.Role.objects.all() ) def test(request): if request.method == "GET": form = TestForm() context = { "form":form, } return render(request,"test.html",context) else: form = TestForm(request.POST) if form.is_valid(): # print(form.cleaned_data) models.UserInfo.objects.create(**form.cleaned_data) return redirect("http://www.baidu.com") context = { "form":form, } return render(request,"test.html",context)
结果与上一致。
4、之前做的form，有cleaned_xxx,clean,xss
# -*- coding:utf-8 -*- from django.forms import Form,fields,widgets from django.core.exceptions import ValidationError import time from blog import models class RegisterForm(Form): username = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control"})) email = fields.EmailField(widget=widgets.TextInput(attrs={"class":"form-control"})) password = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control","type":"password"})) password2 = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control","type":"password"})) avatar = fields.FileField(widget=widgets.FileInput(attrs={"class":"f1","id":"imgSelect"})) code = fields.CharField(widget=widgets.TextInput(attrs={"class":"form-control"})) nickname = fields.CharField(required=False,widget=widgets.TextInput(attrs={"class":"form-control"})) create_time = fields.DateTimeField(required=False) # 传入request是为了检查session中的code字段 def __init__(self,request,*args,**kwargs): # 传入request super(RegisterForm, self).__init__(*args,**kwargs) self.request = request def clean_code(self): input_code = self.cleaned_data["code"] session_code = self.request.session.get("code") if input_code.upper() != session_code.upper(): raise ValidationError("验证码错误") return input_code # 检出用户名是否已被占用 def clean_username(self): username = self.cleaned_data["username"] if models.UserInfo.objects.filter(username=username): raise ValidationError("该用户已被占用") return username # 检出邮箱是否已被占用 def clean_email(self): email = self.cleaned_data["email"] if models.UserInfo.objects.filter(email=email): raise ValidationError("该邮箱已被占用") return email # 检出nickname是否已被占用 def clean_nickname(self): nickname = self.cleaned_data["nickname"] if models.UserInfo.objects.filter(nickname=nickname): raise ValidationError("该昵称已被占用") return nickname def clean(self): # 检查两次密码是否一致 p1 = self.cleaned_data.get("password") p2 = self.cleaned_data.get("password2") if p1 != p2: self.add_error("password2", ValidationError("密码不一致")) # raise ValidationError("密码不一致") else: self.cleaned_data.pop("password2",None) # 如果一致，则去除password2，只保留password，为了与数据库字段一致（数据库只有password） # return self.cleaned_data # return None # 两者均可 # 如无创建时间，添加创建时间 # if not self.cleaned_data.get("create_time"): # self.cleaned_data["create_time"] = time.strftime("%Y-%m-%d") # 如无nickname，添加nickname if not self.cleaned_data.get("nickname"): self.cleaned_data["nickname"] = self.cleaned_data.get("username","")+str(int(time.time())) # 如果验证码正确，去除code，目的是与数据库字段一致（数据库没code） if self.cleaned_data.get("code"): self.cleaned_data.pop("code") return self.cleaned_data class ArticleForm(Form): title = fields.CharField(max_length=64) content = fields.CharField( widget=widgets.Textarea(attrs={"id":"i1"}) ) def clean_content(self): old = self.cleaned_data["content"] from utils.xss import xss return xss(old) # from bs4 import BeautifulSoup # soup = BeautifulSoup(old,"html.parser") # valid_tag = { # "p":["class","id"], # "img":["src"], # "div":["class"], # } # tags = soup.find_all() # for tag in tags: # if tag.name not in valid_tag: # tag.decompose() # 删除整个标签 # # tag.clear() # 删除标签里的内容 # if tag.attrs: # 有些是空字典 # for k in list(tag.attrs.keys()): # {"id":"i1","a"=123,"b"=999} # if k not in valid_tag[tag.name]: # del tag.attrs[k] # 删除属性 # # content_str = soup.decode() # return content_str
from bs4 import BeautifulSoup def xss(old): soup = BeautifulSoup(old, "html.parser") valid_tag = { "p": ["class", "id"], "img": ["src"], "div": ["class"], "span":["style"], } tags = soup.find_all() for tag in tags: if tag.name not in valid_tag: tag.decompose() # 删除整个标签 # tag.clear() # 删除标签里的内容 if tag.attrs: # 有些是空字典 for k in list(tag.attrs.keys()): # {"id":"i1","a"=123,"b"=999} if k not in valid_tag[tag.name]: del tag.attrs[k] # 删除属性 content_origin = soup.decode() content_text = soup.get_text() return content_origin,content_text
