Django之form
一. Django的Form主要功能：
#1. 生成用户标签 #2. HTML Form 天机保留上次提交数据 #3. 验证数据（显示错误信息） #4. 初始化页面显示内容
二.简单使用
1. urls.py
url(r'^login/',views.login), url(r'^ajax_login/',views.ajax_login), url(r'^test/',views.test), url(r'^register/',views.register)
2.views.py
from django.shortcuts import render,redirect,HttpResponse from django.forms import Form from django.forms import fields from django.forms import widgets class LoginForm(Form): user = fields.CharField(required=True) pwd = fields.CharField(min_length=5) def login(request): if request.method == 'GET': return render(request,'login.html') else: obj = LoginForm(request.POST) if obj.is_valid(): print(obj.cleaned_data) return redirect('http://www.baidu.com') return render(request,'login.html',{'obj':obj}) def ajax_login(request): import json ret = {'status':True,'msg':None} obj = LoginForm(request.POST) if obj.is_valid(): print(obj.cleaned_data) else: #print(obj.errors) #obj.errors对象 ret['status'] = False ret['msg'] = obj.errors v = json.dumps(ret) return HttpResponse(v) class TestForm(Form): t1 = fields.CharField(required=True,max_length=5,min_length=3, error_messages={ 'required':'不能为空', 'max_length':'太长', 'min_length':'太短', } ) t2 = fields.EmailField() def test(request): if request.method == 'GET': obj = TestForm() return render(request,'test.html',{'obj':obj}) else: obj = TestForm(request.POST) if obj.is_valid(): print(obj.cleaned_data) else: print(obj.errors) return render(request,'test.html',{'obj':obj}) class RegiterForm(Form): user = fields.CharField(min_length=3) email = fields.EmailField() password = fields.CharField(min_length=3) phone = fields.RegexField('139\d+') def register(request): if request.method == 'GET': obj = RegiterForm() return render(request,'register.html',{'obj':obj}) else: obj = RegiterForm(request.POST) if obj.is_valid(): print(obj.cleaned_data) else: print(obj.errors) return render(request,'register.html',{'obj':obj})
3. *.html
login.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>登录</title> </head> <body> <h1>用户登录</h1> <form id="f1" action="/login/" method="POST"> {% csrf_token %} <p> <input type="text" name="user" />{{ obj.errors.user.0 }} </p> <p> <input type="password" name="pwd" />{{ obj.errors.pwd.0 }} </p> <input type="submit" value="提交" /> <a onclick="submitForm();">Ajax提交</a> </form> <script src="/static/jquery-1.12.4.js"></script> <script> function submitForm() { $('.c1').remove(); $.ajax({ url:'/ajax_login/', type:'POST', data:$('#f1').serialize(), // user=alex&pwd=456&csrftoen=dfdf\ dataType:"JSON", success:function (arg) { console.log(arg); if(arg.status){ }else{ $.each(arg.msg,function(index,value){ console.log(index,,value); var tag = document.createElement('span'); tag.innerHTML = value[0]; tag.className = 'c1'; $('#f1').find('input[name"'+ index + '"]').after(tag); }) } } }) } </script> </body> </html>
test.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/test/" method="POST" novalidate> {% csrf_token %} <p> {{ obj.t1 }}{{ obj.errors.t1.0 }} </p> <p> {{ obj.t2 }}{{ obj.errors.t2.0 }} </p> <input type="submit" value="提交" /> </form> </body> </html>
register.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/register/" method="POST" novalidate> {% csrf_token %} <p> {{ obj.user }}{{ obj.errors.user.0 }} </p> <p> {{ obj.email }}{{ obj.errors.email.0 }} </p> <p> {{ obj.password }}{{ obj.errors.password.0 }} </p> <p> {{ obj.phone }}{{ obj.errors.phone.0 }} </p> <input type="submit" value="提交"> </form> </body> </html>
三. Form类
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 ...
注：UUID是根据MAC以及当前时间等创建的不重复的随机字符串
>>> import uuid # make a UUID based on the host ID and current time >>> uuid.uuid1() # doctest: +SKIP UUID('a8098c1a-f86e-11da-bd1a-00112444be1e') # make a UUID using an MD5 hash of a namespace UUID and a name >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org') UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e') # make a random UUID >>> uuid.uuid4() # doctest: +SKIP UUID('16fd2706-8baf-433b-82eb-8c7fada847da') # make a UUID using a SHA-1 hash of a namespace UUID and a name >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org') UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d') # make a UUID from a string of hex digits (braces and hyphens ignored) >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}') # convert a UUID to a string of hex digits in standard form >>> str(x) '00010203-0405-0607-0809-0a0b0c0d0e0f' # get the raw 16 bytes of the UUID >>> x.bytes b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f' # make a UUID from a 16-byte string >>> uuid.UUID(bytes=x.bytes) UUID('00010203-0405-0607-0809-0a0b0c0d0e0f')
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
四. 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 # )
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.ChoiceField( # choices=((1, '上海'), (2, '北京'),), initial=2, widget=widgets.Select ) def __init__(self, *args, **kwargs): super(MyForm,self).__init__(*args, **kwargs) # self.fields['user'].widget.choices = ((1, '上海'), (2, '北京'),) # 或 self.fields['user'].widget.choices = models.Classes.objects.all().value_list('id','caption')
方式二：
使用django提供的ModelChoiceField和ModelMultipleChoiceField字段来实现
from django import forms from django.forms import fields from django.forms import widgets from django.forms import models as form_model from django.core.exceptions import ValidationError from django.core.validators import RegexValidator class FInfo(forms.Form): authors = form_model.ModelMultipleChoiceField(queryset=models.NNewType.objects.all()) # authors = form_model.ModelChoiceField(queryset=models.NNewType.objects.all())
五. 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'}))
方法三：自定义方法
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]+$', 'Enter a valid extension.', 'invalid')], ) email = fields.EmailField() def clean_username(self): """ Form中字段中定义的格式匹配完之后，执行此方法进行验证 :return: """ value = self.cleaned_data['username'] if "666" in value: raise ValidationError('666已经被玩烂了...', 'invalid') return value
方式四：同时生成多个标签进行验证
from django.forms import Form from django.forms import widgets from django.forms import fields from django.core.validators import RegexValidator ############## 自定义字段 ############## class PhoneField(fields.MultiValueField): def __init__(self, *args, **kwargs): # Define one message for all fields. error_messages = { 'incomplete': 'Enter a country calling code and a phone number.', } # Or define a different message for each field. f = ( fields.CharField( error_messages={'incomplete': 'Enter a country calling code.'}, validators=[ RegexValidator(r'^[0-9]+$', '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]
六. 初始化数据
在Web应用程序中开发编写功能时，时常用到获取数据库中的数据并将值初始化在HTML中的标签上。
1.form
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() city = fields.ChoiceField( choices=((1, '上海'), (2, '北京'),), widget=widgets.Select )
2.view
from django.shortcuts import render, redirect from .forms import MyForm def index(request): if request.method == "GET": values = {'user': 'root', 'city': 2} obj = MyForm(values) return render(request, 'index.html', {'form': obj}) elif request.method == "POST": return redirect('http://www.google.com') else: return redirect('http://www.google.com')
3.hrml
<form method="POST" enctype="multipart/form-data"> {% csrf_token %} <p>{{ form.user }} {{ form.user.errors }}</p> <p>{{ form.city }} {{ form.city.errors }}</p> <input type="submit"/> </form>
#其它
#Form组件 - 校验 - 保留上次输入内容（生成HTML标签） class Foo(Form)： user = fields.CharField()# 验证规则，HTML标签插件 obj = Foo(data = request.POST) # 有HTML标签，含有错误信息 obj = Foo(intial = {}) # 只有HTML标签 obj.is_valid() obj.errors obj.cleaned_data a. 多对多 - ChoiceField(可被替代) - MultiplChoiceField b. 常用插件 - CheckBox - radio - input - textarea - File Select框： 单选 cls_id = fields.IntegerField( # widget=widgets.Select(choices=[(1,'上海'),(2,'北京')]) widget=widgets.Select(choices=models.Classes.objects.values_list('id','title'),attrs={'class': 'form-control'}) ) cls_id = fields.ChoiceField( choices=models.Classes.objects.values_list('id','title'), widget=widgets.Select(attrs={'class': 'form-control'}) ) obj = FooForm({'cls_id':1}) 多选 xx = fields.MultipleChoiceField( choices=models.Classes.objects.values_list('id','title'), widget=widgets.SelectMultiple ) obj = FooForm({'cls_id':[1,2,3]}) 修复Bug，刷新无法动态显示数据库内容： 方式一： class TeacherForm(Form): tname = fields.CharField(min_length=2) # xx = form_model.ModelMultipleChoiceField(queryset=models.Classes.objects.all()) # xx = form_model.ModelChoiceField(queryset=models.Classes.objects.all()) 方式二： class TeacherForm(Form): tname = fields.CharField(min_length=2) xx = fields.MultipleChoiceField( widget=widgets.SelectMultiple ) def __init__(self,*args,**kwargs): super(TeacherForm,self).__init__(*args,**kwargs) self.fields['xx'].widget.choices = models.Classes.objects.values_list('id','title') c. 扩展 - is_valid - 字段 = 默认正则表达式 - 额外的正则 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')], ) - clean_字段，必须返回值 - clean() 有返回值：cleaned_data = 返回值 无返回值：cleaned_data = 原来的值
#2. 钩子
from django.core.exceptions import ValidationError class TestForm(Form): user = fields.CharField(validators=[]) pwd = fields.CharField() def clean_user(self): v = self.cleaned_data['user'] if models.Student.objects.filter(name=v).count(): raise ValidationError('用户名已经存在') return self.cleaned_data['user'] def clean_pwd(self): return self.cleaned_data['pwd'] def clean(self): # user = self.cleaned_data.get('user') # email = self.cleaned_data.get('email') # if models.Student.objects.filter(user=user,email=email).count(): # raise ValidationError('用户名和邮箱联合已经存在') return self.cleaned_data # def _post_clean(self): #当做补充 # """ # An internal hook for performing additional cleaning after form cleaning # is complete. Used for model validation in model forms. # """ # pass #----------------------------------------------------------------------- class TestForm(Form): # t1 = fields.CharField( # widget=widgets.Textarea(attrs={}) # ) # # # t2 = fields.CharField( # widget=widgets.CheckboxInput # ) # # t3 = fields.MultipleChoiceField( # choices=[(1,'篮球'),(2,'足球'),(3,'溜溜球')], # widget=widgets.CheckboxSelectMultiple # ) # # t4 = fields.ChoiceField( # choices=[(1,'篮球'),(2,'足球'),(3,'溜溜球')], # widget=widgets.RadioSelect # ) # t5 = fields.FileField( # widget=widgets.FileInput # ) # def clean_t1(self): # pass
