Django之Form组件
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
小试牛刀
1、创建Form类
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)
)
2、View函数处理
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')
3、生成HTML
<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>
<form method="POST" enctype="multipart/form-data"> {% csrf_token %} {{ form.xxoo.label }} {{ form.xxoo.id_for_label }} {{ form.xxoo.label_tag }} {{ form.xxoo.errors }} <p>{{ form.user }} {{ form.user.errors }}</p> <input type="submit" /> </form>
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
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())
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]
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、Views
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、HTML
<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>
出自：老司机
第一次
最简单的浅入和最纯真的理解
from django.shortcuts import render,redirect,HttpResponse from django.forms import Form from django.forms import fields # Create your views here. class LoginForm(Form): #必须继承Form #fields里面有一大堆正则表达式 # email=fields.EmailField() # ip=fields.GenericIPAddressField() # num=fields.IntegerField() username=fields.CharField( max_length=18, min_length=6, required=True, #不能为空 error_messages={ #默认错误信息是英文的,这里可以自定制中文错误信息 'required':'用户名不能为空', 'min_length':'用户名不能少于6位', 'max_length':'用户名不能大于18位' } ) password=fields.CharField(max_length=16,required=True) def login(request): if request.method=='GET': return render(request,'login.html') else: obj=LoginForm(request.POST)#多么牛逼的一个对象啊 # ret=obj.is_valid() #ret的值就是True或False,内部会完成校验 if obj.is_valid(): print(obj.cleaned_data) #obj.cleaned_data是一个字典,里面装的是用户填的所有的信息 #直接models.UserInfo.object.creat(**obj.cleaned_data)就完成注册了 else: print(obj.errors) #obj.errors是一个对象,对象中有一个__str__方法 #如果有错误信息，我们只拿他的第一个，如下,但是在后台拿没有意义 # print(obj.errors['username'][0]) # print(obj.errors['password'][0]) return render(request,'login.html',{'obj':obj}) ''' 总结： 1.定义规则 from django.forms import Form from django.forms import fields class LoginForm(Form): username=fields.CharField(max_length=18,min_length=6,required=True,error_messages=..) password=fields.CharField(max_length=16,required=True) 2.使用 obj=LoginForm(request.POST) #开始校验验 v=obj.is_valid() #校验成功True,不成功False 注意：1.form表单的name属性名字和LoginForm下的字段名必须保持一 致这是确保能校验的根本; 2.LoginForm里面写几个规则就会验证几个规则,这样才安全,因 为提交的个数可以在前端进行修改,审查元素->选中input标签-> 右击Edit..->复制一个就会多了一个新的input标签; obj.errors #所有错误信息 obj.cleaned_data #所有的正确信息 '''
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/login/" method="POST"> {% csrf_token %} <p>用户：<input type="text" name="username">{{ obj.errors.username.0 }}</p> <p>密码：<input type="password" name="password">{{ obj.errors.password.0 }}</p> <input type="submit" value="提交"> </form> </body> </html>
注：不要忘记路由系统
第二次
1、Ajax版登陆,
class LoginForm2(Form): user=fields.CharField(required=True) pwd=fields.CharField(min_length=18) def login2(request): if request.method=='GET': return render(request,'login2.html') else: obj=LoginForm2(request.POST) if obj.is_valid(): print(obj.cleaned_data) return redirect('htttp://www.baidu.com') return render(request,'login2.html',{'obj':obj}) def ajax_login(request): import json ret={'status':True,'msg':None} obj=LoginForm2(request.POST) if obj.is_valid(): print(obj.cleaned_data) else: ret['status']=False ret['msg']=obj.errors v=json.dumps(ret) return HttpResponse(v)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h3>用户登录ss</h3> <form action="/login2/" method="POST" id="f1"> {% 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="submitFrom();">提交</a> </form> <script src="/static/jquery-3.2.1.js"></script> <script> function submitFrom() { $('.c1').remove(); $.ajax({ url:'/ajax_login/', type:'POST', data:$('#f1').serialize(),//user=alex&pwd=1233&csrftoke=sadfsf,之前传的字典也是被转成功了这个格式 dataType:'JSON', success:function (arg) { console.log(arg); if(arg.status){ console.log(ok); }else { $.each(arg.msg,function (index,value) { //循参数环记一下 console.log(index,value); var tag=document.createElement('span'); //js创建标签 tag.innerHTML=value[0]; //js给标签写文本 tag.className='c1'; //js给标签定义类 $('#f1').find('input[name="'+index+'"]').after(tag); //字符串神奇的拼接方式 }) } } }) } </script> </body> </html>
注：新的Aja知识点,还有细节知识点,可以直接jason.dumps一个对象不要忘记路由系统
2、obj.is_valid原理
声明：这个理有点糙
''' obj.is_valid()原理： 1.LoginForm2实例化时，会有下面的字典生成 self.fields={ 'user':正则表达式 'pwd':正则表达式 }有了这个字典就可以进行校验了 2.循环self.fields flag=True errors #容器，用来放错误信息 cleaned_data #容器，用来放正确信息 for k,v in self.fields.items(); #首先是'user'与'user'对应的正则表达式 input_value=request.POST.get(k) #从前端传来的之中拿到user的值 正则表达式和input_value进行匹配 匹配成功继续匹配或拿到cleaned_data进行下一步 匹配失败flag=False,拿到errors return flag '''
3、form组件生成HTML标签原理
声明：理太糙
'''
生成HTML标签的原理：
class TestForm(Form):
t1=fields.CharField()
在前端如果有{{obj.t1}}的话就会生成一个input标签
因为在fielsd内部最后有个__str__方法就是生成一个
"<input type='text' name=t1>" 之类的字符串，如
果t1字段内有值的话，生成的这个input标签就会默认
多一个value属性。
'''
4、form表单与学员管理再见
models
from django.db import models
class Classes(models.Model):
title=models.CharField(max_length=32)
class Student(models.Model):
name=models.CharField(max_length=32)
email=models.CharField(max_length=32)
age=models.IntegerField(max_length=32)
cls=models.ForeignKey('Classes')
class Teacher(models.Model):
tname=models.CharField(max_length=32)
c2t=models.ManyToManyField('Classes')
urls代码
from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
url(r'^class_list/', views.class_list),
url(r'^add_class/', views.add_class),
url(r'^edit_class/(\d+)/', views.edit_class),
url(r'^student_list/', views.student_list),
url(r'^add_student/', views.add_student),
url(r'^edit_student/(\d+)/', views.edit_student),
url(r'^teacher_list/', views.teacher_list),
url(r'^add_teacher/', views.add_teacher),
url(r'^edit_teacher/(\d+)/', views.edit_teacher),
]
views代码
from django.shortcuts import render,HttpResponse,redirect
from app01 import models
from django.forms import Form
from django.forms import fields
from django.forms import widgets
class ClassForm(Form):
title=fields.RegexField('全栈\d+')
#注意:类的字段名,和前端传来的键名,还有数据库的字段名最好一致,省事
def class_list(request):
cls_list=models.Classes.objects.all()
return render(request,'class_list.html',{'cls_list':cls_list})
def add_class(request):
if request.method=='GET':
obj=ClassForm()
return render(request,'add_class.html',{'obj':obj})
else:
obj=ClassForm(request.POST)
if obj.is_valid():
models.Classes.objects.create(**obj.cleaned_data)
return redirect('/class_list/')
def edit_class(request,nid):
if request.method=='GET':
row=models.Classes.objects.filter(id=nid).first()
#让页面显示初始值
#obj=ClassForm({'title':row.title})
#上式默认就是obj = ClassForm(data={'title':row.title})
#但是data会在内部进行一次验证，会把错误信息也带到前端去
#如果要避免这种情况的话就得用innitital=...
obj=ClassForm(initial={'title':row.title})
return render(request,'edit_class.html',{'nid':nid,'obj':obj})
else:
obj=ClassForm(request.POST)
if obj.is_valid():
models.Classes.objects.filter(id=nid).update(**obj.cleaned_data)
return redirect('/class_list/')
return render(request,'edit_class.html',{'nid':nid,'obj':obj})
class StudentForm(Form):
name=fields.CharField(
min_length=2,
max_length=6,
widget=widgets.TextInput(attrs={'class': 'form-control'})
#widget选择生成的标签,还可以给其增加属性
)
email=fields.EmailField(widget=widgets.TextInput(attrs={'class':'form-control'}))
age=fields.IntegerField(
min_value=18,
max_value=25,
widget=widgets.TextInput(attrs={'class': 'form-control'})
)
cls_id=fields.IntegerField(
# widget=widgets.Select(choices=[(1,'上海'),(2,'北京')])标准姿势
widget=widgets.Select(choices=models.Classes.objects.values_list('id','title'),attrs={'class': 'form-control'})
)
def student_list(request):
stu_list=models.Student.objects.all()
return render(request,'student_list.html',{'stu_list':stu_list})
def add_student(request):
if request.method=='GET':
obj=StudentForm()
return render(request,'add_student.html',{'obj':obj})
else:
obj=StudentForm(request.POST)
if obj.is_valid():
models.Student.objects.create(**obj.cleaned_data)
return redirect('/student_list/')
return render(request,'add_student.html',{'obj':obj})
def edit_student(request,nid):
if request.method=='GET':
row=models.Student.objects.filter(id=nid).values('name','email','age','cls_id').first() ###记住这个式子
obj=StudentForm(initial=row)
return render(request,'edit_student.html',{'nid':nid,'obj':obj})
else:
obj=StudentForm(request.POST)
if obj.is_valid():
models.Student.objects.filter(id=nid).update(**obj.cleaned_data)
return redirect('/student_list/')
return render(request,'edit_student.html',{'nis':nid,'obj':obj})
class TeacherForm(Form):
tname=fields.CharField(min_length=2)
xx=fields.MultipleChoiceField(
# choices=models.Classes.objects.values_list('id','title'),
widget=widgets.SelectMultiple
)
def __init__(self,*args,**kwargs): #解决班级列表不能实时跟新的bug
super(TeacherForm,self).__init__(*args,**kwargs)
self.fields['xx'].choices=models.Classes.objects.values_list('id','title')
#obj=TeacherForm()
#1.找到所有字段
#2.self.fields={
# tname:fields.CharField(min_length=2)
# }
def teacher_list(request):
tea_list=models.Teacher.objects.all()
return render(request,'teacher_list.html',{'tea_list':tea_list})
def add_teacher(request):
if request.method=='GET':
obj=TeacherForm()
return render(request,'add_teacher.html',{'obj':obj})
else:
print(123)
obj=TeacherForm(request.POST)
if obj.is_valid():
xx=obj.cleaned_data.pop('xx')
row=models.Teacher.objects.create(**obj.cleaned_data)
row.c2t.add(*xx)
return redirect('/teacher_list/')
return render(request,'add_teacher.html',{'obj':obj})
def edit_teacher(request,nid):
if request.method=="GET":
row=models.Teacher.objects.filter(id=nid).first()
class_ids=row.c2t.values_list('id')
print(class_ids)
id_list=list(zip(*class_ids))[0] if list(zip(*class_ids)) else []
# obj=TeacherForm(initial={'tname':row.tname,'xx':[1,2,3]})
obj=TeacherForm(initial={'tname':row.tname,'xx':id_list})
return render(request,'edit_teacher.html',{'obj':obj,'nid':nid})
else:
obj=TeacherForm(request.POST)
if obj.is_valid():
print(obj.cleaned_data)
xx = obj.cleaned_data.pop('xx')
row=models.Teacher.objects.filter(id=nid).update(**obj.cleaned_data)
print(row)
teacher_row=models.Teacher.objects.filter(id=nid).first()
teacher_row.c2t.set(xx) #如果是add或者是remove的话后面是(*xx)
else:
print(obj.errors)
return redirect('/teacher_list/')
class_list.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>班级列表</h3>
<a href="/add_class/">添加</a>
<ul>
{% for row in cls_list %}
<li>{{ row.title }} <a href="/edit_class/{{ row.id }}/">编辑</a> </li>
{% endfor %}
</ul>
</body>
</html>
add_class.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>添加班级</h3>
<form action="/add_class/" method="POST" novalidate>
{% csrf_token %}
<p>{{ obj.title }} {{ obj.errors.title.0 }}</p>
<input type="submit" value="提交">
</form>
</body>
</html>
edit_class.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>编辑班级</h3>
<form action="/edit_class/{{ nid }}/" method="POST">
{% csrf_token %}
<p>{{ obj.title }} {{ obj.errors.title.0 }}</p>
<input type="submit" value="提交">
</form>
</body>
</html>
student_list.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>学生列表</h3>
<a href="/add_student/">添加</a>
<ul>
{% for row in stu_list %}
<li>{{ row.name }}-{{ row.email }}-{{ row.age }}-{{ row.cls_id }}-{{ row.cls.title }} <a href="/edit_student/{{ row.id }}/">编辑</a> </li>
{% endfor %}
</ul>
</body>
</html>
add_student.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>添加学生</h3>
<form action="/add_student/" method="POST">
{% csrf_token %}
<p>{{ obj.name }}</p>
<p>{{ obj.email }}</p>
<p>{{ obj.age }}</p>
<p>{{ obj.cls_id }}</p>
<input type="submit" value="提交">
</form>
</body>
</html>
edit_student.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<link rel="stylesheet" href="/static/bootstrap-3.3.5-dist/css/bootstrap.css"/>
</head>
<body>
<div style="width: 500px;margin: 0 auto;">
<form class="form-horizontal" method="POST" action="/edit_student/{{ nid }}/">
{% csrf_token %}
<div class="form-group">
<label class="col-sm-2 control-label">姓名：</label>
<div class="col-sm-10">
{{ obj.name }}
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">邮箱：</label>
<div class="col-sm-10">
{{ obj.email }}
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">年龄：</label>
<div class="col-sm-10">
{{ obj.age }}
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">班级：</label>
<div class="col-sm-10">
{{ obj.cls_id }}
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<input type="submit" class="btn btn-default" value="提交" />
</div>
</div>
</form>
</div>
</body>
</html>
teacher_list.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>老师列表</h3>
<a href="/add_teacher/">添加</a>
<table cellspacing="0" cellpadding="5px" border="1px">
<thead>
<tr>
<th>ID</th>
<th>老师姓名</th>
<th>所受班级</th>
<th>操作</th>
</tr>
</thead>
<tbody>
{% for row in tea_list %}
<tr>
<td>{{ row.id }}</td>
<td>{{ row.tname }}</td>
<td>
{% for row in row.c2t.all %}
{{ row.title }}
{% endfor %}
</td>
<td><a href="/edit_teacher/{{ row.id }}/">编辑</a></td>
</tr>
{% endfor %}
</tbody>
</table>
</body>
</html>
add_teacher.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="/add_teacher/" method="POST">
{% csrf_token %}
<p>老师姓名：{{ obj.tname }}</p>
<p>任课班级：{{ obj.xx }}</p>
<input type="submit" value="提交">
</form>
</body>
</html>
edit_teacher.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>编辑老师</h3>
<form action="/edit_teacher/{{ nid }}/" method="POST">
{% csrf_token %}
<p>老师姓名：{{ obj.tname }}{{ obj.tname.errors.0 }}</p>
<p>教授班级：{{ obj.xx }}{{ obj.xx.errors.0 }}</p>
<input type="submit" value="提交">
</form>
</body>
</html>
5、字段参数的简单使用，直接上图了
后端代码
前端代码
前端还有个更简单的代码：obj.as_p完事这是生成P标签里面有input标签
类似的还有：<ul> {{obj.as_ul}} </ul>
<table> {{obj.as_table}} </table>
第三次
1、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]})
2、修复编辑老师不能实时显示班级Bug，刷新无法动态显示数据库内容：
方式一：虽然简单，但是局限性比较大，依赖models需要在models类里面加__str__方法，如果数据库跟主代码分离的话就不能用了
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
3、另外一种自定义正则表达式的方法
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')],
)
4、自定制检查机制（源码里为我们留好的）
from django.core.exceptions import ValidationError
class TestForm2(Form):
user=fields.ChoiceField()
pwd=fields.CharField()
def clean_user(self): #检查user字段下有没有这个方法有的话就执行,必须要有返回值
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):
"""
Hook for doing any extra form-wide cleaning after Field.clean() has been
called on every field. Any ValidationError raised by this method will
not be associated with a particular field; it will have a special-case
association with the field named '__all__'.
"""
#在进行到这个方法的时候obj.cleaned_data中已经拿到全部的东西
#我们可以在这里进行整体校验,比如可以增加联合唯一索引的限制
#有返回值：cleaned_data = 返回值
#无返回值：cleaned_data = 原来的值
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):
"""
An internal hook for performing additional cleaning after form cleaning
is complete. Used for model validation in model forms.
"""
#英语自己去翻译
pass
5、上传文件
注意：FORM表单提交文件要有一个参数enctype="multipart/form-data"
#上传文件之原生input=file版
def f1(request):
if request.method=='GET':
return render(request,'f1.html')
else:
import os
file_obj=request.FILES.get('fafafa')
f=open(os.path.join('static',file_obj.name),'wb')
for chunk in file_obj.chunks():#那文本一块一块拿
f.write(chunk)
f.close()
return render(request,'f1.html')
#f1.html代码
<form action="/f1/" method="POST" enctype="multipart/form-data">
{% csrf_token %}
<input type="text" name="user">
<input type="file" name="fafafa">
<input type="submit" value="提交">
</form>
#上传文件之FORM表单生成HTML标签版
class F2Form(Form):
user=fields.CharField()
fafafa=fields.FileField()
def f2(request):
if request.method=="GET":
obj=F2Form()
return render(request,'f2.html',{'obj':obj})
else:
obj=F2Form(data=request.POST,files=request.FILES)
if obj.is_valid():
file_obj=obj.cleaned_data.get('fafafa')
with open('static/a','wb')as f:
for chunk in file_obj.chunks():
f.write(chunk)
return render(request, 'f2.html', {'obj': obj})
#f2.html代码
<form action="/f2/" method="POST" enctype="multipart/form-data">
{% csrf_token %}
{{ obj.user }}
{{ obj.fafafa }}
<input type="submit" value="提交">
</form>
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