【django】form
阿新 • • 發佈：2018-06-07
表單 redirect 對象 view radio F5 類變量 stat rabl 
form
組件組要功能：
- 生成HTML標簽
- 驗證用戶數據（顯示錯誤信息）
- HTML Form提交保留上次提交數據
- 初始化頁面顯示內容
1.創建Form類時，主要涉及到 【字段】 和 【插件】，字段用於對用戶請求數據的驗證，插件用於自動生成HTML;
① Django內置字段如下：
Field
required=True, 是否允許為空
widget=None, HTML插件
label=None, 用於生成Label標簽或顯示內容
initial=None, 初始值
help_text=‘‘, 幫助信息(在標簽旁邊顯示)
error_messages=None, 錯誤信息 {‘required‘: ‘不能為空‘, ‘invalid‘: ‘格式錯誤‘}
show_hidden_initial=False, 是否在當前插件後面再加一個隱藏的且具有默認值的插件（可用於檢驗兩次輸入是否一直）
validators=[], 自定義驗證規則
localize=False, 是否支持本地化
disabled=False, 是否可以編輯
label_suffix=None Label內容後綴
CharField(Field)
max_length=None, 最大長度
min_length=None, 最小長度
strip=True 是否移除用戶輸入空白
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, 總長度
decimal_places=None, 小數位長度
BaseTemporalField(Field)
input_formats=None 時間格式化
DateField(BaseTemporalField) 格式：2015-09-01
TimeField(BaseTemporalField) 格式：11:12
DateTimeField(BaseTemporalField)格式：2015-09-01 11:12
DurationField(Field) 時間間隔：%d %H:%M:%S.%f
...
RegexField(CharField)
regex, 自定制正則表達式
max_length=None, 最大長度
min_length=None, 最小長度
error_message=None, 忽略，錯誤信息使用 error_messages={‘invalid‘: ‘...‘}
EmailField(CharField)
...
FileField(Field)
allow_empty_file=False 是否允許空文件
ImageField(FileField)
...
註：需要PIL模塊，pip3 install Pillow
以上兩個字典使用時，需要註意兩點：
- form表單中 enctype="multipart/form-data"
- view函數中 obj = MyForm(request.POST, request.FILES)
URLField(Field)
...
BooleanField(Field)
...
NullBooleanField(BooleanField)
...
ChoiceField(Field)
...
choices=(), 選項，如：choices = ((0,‘上海‘),(1,‘北京‘),)
required=True, 是否必填
widget=None, 插件，默認select插件
label=None, Label內容
initial=None, 初始值
help_text=‘‘, 幫助提示
ModelChoiceField(ChoiceField)
... django.forms.models.ModelChoiceField
queryset, # 查詢數據庫中的數據
empty_label="---------", # 默認空顯示內容
to_field_name=None, # HTML中value的值對應的字段
limit_choices_to=None # ModelForm中對queryset二次篩選
ModelMultipleChoiceField(ModelChoiceField)
... django.forms.models.ModelMultipleChoiceField
TypedChoiceField(ChoiceField)
coerce = lambda val: val 對選中的值進行一次轉換
empty_value= ‘‘ 空值的默認值
MultipleChoiceField(ChoiceField)
...
TypedMultipleChoiceField(MultipleChoiceField)
coerce = lambda val: val 對選中的每一個值進行一次轉換
empty_value= ‘‘ 空值的默認值
ComboField(Field)
fields=() 使用多個驗證，如下：即驗證最大長度20，又驗證郵箱格式
fields.ComboField(fields=[fields.CharField(max_length=20), fields.EmailField(),])
MultiValueField(Field)
PS: 抽象類，子類中可以實現聚合多個字典去匹配一個值，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) 文件選項，目錄下文件顯示在頁面中
path, 文件夾路徑
match=None, 正則匹配
recursive=False, 遞歸下面的文件夾
allow_files=True, 允許文件
allow_folders=False, 允許文件夾
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時候，可解析為192.0.2.1， PS：protocol必須為both才能啟用
SlugField(CharField) 數字，字母，下劃線，減號（連字符）
...
UUIDField(CharField) uuid類型
...
- 常用字段(重點）
ChoiceField ***** MultipleChoiceField CharField IntegerField DecimalField DateField DateTimeField EmailField GenericIPAddressField FileField RegexField
② Django內置插件：
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
常用選擇插件
# 單radio，值為字符串 # user = fields.CharField( # initial=2, # widget=widgets.RadioSelect(choices=((1,‘上海‘),(2,‘北京‘),)) # ) # 單radio，值為字符串 # user = fields.ChoiceField( # choices=((1, ‘上海‘), (2, ‘北京‘),), # initial=2, # widget=widgets.RadioSelect # ) # 單select，值為字符串 # user = fields.CharField( # initial=2, # widget=widgets.Select(choices=((1,‘上海‘),(2,‘北京‘),)) # ) # 單select，值為字符串 # user = fields.ChoiceField( # choices=((1, ‘上海‘), (2, ‘北京‘),), # initial=2, # widget=widgets.Select # ) # 多選select，值為列表 # user = fields.MultipleChoiceField( # choices=((1,‘上海‘),(2,‘北京‘),), # initial=[1,], # widget=widgets.SelectMultiple # ) # 單checkbox # user = fields.CharField( # widget=widgets.CheckboxInput() # ) # 多選checkbox,值為列表 # user = fields.MultipleChoiceField( # initial=[2, ], # choices=((1, ‘上海‘), (2, ‘北京‘),), # widget=widgets.CheckboxSelectMultiple # )
2.表單驗證
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), ]project/urls.py
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‘: ‘用戶不能為空‘, ‘max_length‘: ‘太長了‘, ‘min_length‘: ‘太短了‘, ‘invalid‘: ‘格式不正確‘,#格式不正確都是invalid } ) pwd = fields.CharField( min_length=6, required=True, error_messages={ ‘required‘ : ‘密碼不能為空‘, ‘min_length‘: ‘太短了‘, ‘invalid‘ : ‘密碼格式不正確‘, } ) email = fields.EmailField(required=True, error_messages={ ‘required‘ : ‘郵箱不能為空‘ , ‘invalid‘ : ‘格式需為郵箱格式‘, } ) age = fields.IntegerField( required=True, error_messages={ ‘required‘: ‘年齡不能為空‘, ‘invalid‘ : ‘年齡需為數字‘, } ) 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.檢查是否為空 # 2.檢查格式是否正確 # print(u,p,e,a) obj = F1From(request.POST) # 是否全部驗證成功 if obj.is_valid(): #用戶提交的數據 print(‘驗證成功‘,obj.cleaned_data) return redirect(‘http://www.baidu.com‘) # return render(request,‘f1.html‘,{‘obj‘:obj}) else: print(‘驗證失敗‘,obj.errors) return render(request,‘f1.html‘,{‘obj‘:obj})app02/views.py
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form id="fm" action="/f1.html" method="POST"> <P>用戶: {{ obj.user }}{{ obj.errors.user.0 }}</P>{# 一個輸入項可能包含多種格式錯誤，取第一個 .0 #} <P>密碼: {{ obj.pwd }}{{ obj.errors.pwd.0 }}</P> <P>郵箱: {{ obj.email }}{{ obj.errors.email.0 }}</P> <P>年齡: {{ obj.age }}{{ obj.errors.age.0 }}</P> <input type="submit" value="form提交"/> </form> </body> </html>templates/f1.html
效果展示：
3、初始化默認值——form表單簡單更改單表數據庫數據（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), ]project/urls.py
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(‘驗證成功‘,obj.cleaned_data) # models.UserInfo.objects.create( # username = obj.cleaned_data[‘username‘], # email = obj.cleaned_data[‘email‘], # ) # 後面一句可以直接代替上面語句 models.UserInfo.objects.create(**obj.cleaned_data) return redirect(‘/users/‘) else: print(‘驗證失敗‘,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() # 拿到一個對象 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})app01/views.py
# !/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‘:"用戶不能為空", ‘min_length‘:‘太短了‘, } ) email = fields.EmailField( required=True, error_messages={ ‘required‘: "郵箱不能為空", ‘invalid‘:‘郵箱格式錯誤‘, } )app01/forms.py
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)app01/models.py
<!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 }}">編輯</a></li> {% endfor %} </ul> </body> </html>templates/users.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>用戶：{{ obj.username }}{{ obj.errors.username.0 }}</p> <p>郵箱：{{ obj.email }}{{ obj.errors.email.0 }}</p> <input type="submit" value="提交"/> </form> </body> </html>templates/add_user.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>用戶：{{ obj.username }}{{ obj.errors.username.0 }}</p> <p>郵箱：{{ obj.email }}{{ obj.errors.email.0 }}</p> <input type="submit" value="提交"/> </form> </body> </html>templates/edit.html
效果展示：
4.動態更新實時數據
在使用選擇標簽時，需要註意choices的選項可以從數據庫中獲取，但是由於是靜態字段（類變量） ***獲取的值無法實時更新***，那麽需要自定義構造方法從而達到此目的。
方法一：(推薦)
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), ]project/urls.py
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>非誠勿擾</h1> <P>價格：{{ obj.prive }}</P> <P>人員：{{ obj.user_id }}</P> </body> </html>templates/love.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)app01/models.py
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,‘蘋果‘),(1,‘梨子‘),(2,‘香蕉‘)], #自己創建 # choices= models.UserInfo.objects.values_list(‘id‘,‘username‘) #也可以從數據庫取數據 ) ) prive = fields.IntegerField() def __init__(self,*args,**kwargs): #拷貝所有靜態字段，復制給self.fields (順序：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})app02/views.py
效果展示：
方法二：(依賴於model中的__str__方法，多個slecte框不適用，耦合性太強)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>非誠勿擾</h1> <P>價格：{{ obj.prive }}</P> <P>人員：{{ obj.user_id }}</P> <P>人員：{{ obj.user_id2 }}</P> <!--新增--> </body> </html>templates/love.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app01/models.py
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,‘蘋果‘),(1,‘梨子‘),(2,‘香蕉‘)], #自己創建 # choices= models.UserInfo.objects.values_list(‘id‘,‘username‘) #也可以從數據庫取數據 ) ) 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): #拷貝所有靜態字段，復制給self.fields (順序：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})app02/views.py
效果展示：
5.Ajax提交驗證（驗證；無需上次內容）
- 返回HttpResponse
- 前端：跳轉或錯誤信息
如果想要ajax提交數據到django後臺，對頁面進行跳轉，需要在ajax 中驗證後進行跳轉，在後臺進行跳轉不生效.
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), ]project/urls.py
<!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:狀態，錯誤信息 if (arg.status == ‘錢‘){ window.location.href="http://www.baidu.com" } console.log(arg); } }) }) }) </script> </body> </html>templates/ajax.html
class AjaxForm(forms.Form): prive = fields.IntegerField() user_id = fields.IntegerField( widget=widgets.Select( choices=[(0,‘蘋果‘),(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‘:‘沒錢‘,‘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‘]=‘錢‘ 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))app02/views.py
自定義驗證規則(from組件擴展)
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]+$‘, ‘請輸入數字‘), RegexValidator(r‘^159[0-9]+$‘, ‘數字必須以159開頭‘)],
)
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‘: ‘格式錯誤‘})
基於源碼流程
a. 單字段（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,‘劉皓宸‘),(2,‘楊建‘),]) ) # 自定義方法 clean_字段名 # 必須返回值self.cleaned_data[‘username‘] # 如果出錯：raise ValidationError(‘用戶名已存在‘) def clean_username(self): v = self.cleaned_data[‘username‘] if models.UserInfo.objects.filter(username=v).count(): # 整體錯了 # 自己詳細錯誤信息 raise ValidationError(‘用戶名已存在‘) return v def clean_user_id(self): return self.cleaned_data[‘user_id‘]
b. 整體錯誤驗證（clean_form）
class AjaxForm(forms.Form): username = fields.CharField() user_id = fields.IntegerField( widget=widgets.Select(choices=[(0,‘alex‘),(1,‘劉皓宸‘),(2,‘楊建‘),]) ) # 自定義方法 clean_字段名 # 必須返回值self.cleaned_data[‘username‘] # 如果出錯：raise ValidationError(‘用戶名已存在‘) def clean_username(self): v = self.cleaned_data[‘username‘] if models.UserInfo.objects.filter(username=v).count(): # 整體錯了 # 自己詳細錯誤信息 raise ValidationError(‘用戶名已存在‘) 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(‘整體錯誤信息‘) return self.cleaned_data
【django】form