33.Django ModelForm

2022-09-24 22:22:33

ModelForm

1.ModeForm简单验证

from django.db import models

# Create your models here.

class UserInfo(models.Model):

    # verbose_name 等同于Form类里面的label

    username = models.CharField(verbose_name='用户',max_length=32)

    email = models.EmailField(verbose_name='邮件')

    user_type = models.ForeignKey(verbose_name='类型',to='UserType',to_field='id')

class UserType(models.Model):

    caption = models.CharField(max_length=32)

    def __str__(self):          #打印名称，不写显示的是obj对象

        return self.caption

models.py

model.py

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>Title</title>

</head>

<body>

    <form action="/index/" method="post">

        {% csrf_token %}

        {{ obj.as_p }}

        <input type="submit" value="提交"/>

    </form>

</body>

</html>

index.html

index.html

views.py

from django.shortcuts import render,redirect

from app01 import models

from django import forms

from django.forms import fields

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        model = models.UserInfo  # 去UserInfo类中获取数据

        fields = '__all__'  # __all__ 代指所有字段

        # fields = ['username','email']       #指定显示的字段

        # exclude = ['username']      #不显示的字段

def index(request):

    if request.method == 'GET':

        obj = UserInfoModelForm()

        return render(request,'index.html',{'obj':obj})

    elif request.method == 'POST':

        obj = UserInfoModelForm(request.POST)

        result = obj.is_valid()

        if result:

            print(obj.cleaned_data)             #如果models里没有__str__方法，则user_type获取

                                                        #到的是一个对象，可直接根据对象进行操作

            print(obj.cleaned_data['user_type'])

            # {'username': 'James', 'user_type': < UserType: 超级用户 >, 'email': 'ffd@fdsf.com'}

            # 超级用户

        else:

            print(obj.errors)

        return render(request,'index.html',{'obj':obj})

注：ModelForm最终继承了BaseForm，BaseForm里面具有is_valid方法，所以ModelForm也可以用is_valid进行验证

2.ModelForm组件

ModelForm

    a.  class Meta:

            model,                           # 对应Model的

            fields=None,                     # 字段

            exclude=None,                    # 排除字段

            labels=None,                     # 提示信息　　labels ={'username':'用户名'}可写多个

            help_texts=None,                 # 帮助提示信息    help_texts = {'username':'help info'}

            widgets=None,                    # 自定义插件

            error_messages=None,             # 自定义错误信息（整体错误信息from django.core.exceptions import NON_FIELD_ERRORS）

            field_classes=None               # 自定义字段类 （也可以自定义字段）

            localized_fields=('birth_date',) # 本地化，如：根据不同时区显示数据

            如：

                数据库中

                    2016-12-27 04:10:57

                setting中的配置

                    TIME_ZONE = 'Asia/Shanghai'

                    USE_TZ = True

                则显示：

                    2016-12-27 12:10:57

    b. 验证执行过程

        is_valid -> full_clean -> 钩子 -> 整体错误

    c. 字典字段验证

        def clean_字段名(self):

            # 可以抛出异常

            # from django.core.exceptions import ValidationError

            return "新值"

    d. 用于验证

        model_form_obj = XXOOModelForm()

        model_form_obj.is_valid()

        model_form_obj.errors.as_json()

        model_form_obj.clean()

        model_form_obj.cleaned_data

    e. 用于创建

        model_form_obj = XXOOModelForm(request.POST)

        #### 页面显示，并提交 #####

        # 默认保存多对多

            obj = form.save(commit=True)

        # 不做任何操作，内部定义 save_m2m（用于保存多对多）

            obj = form.save(commit=False)

            obj.save()      # 保存单表信息

            obj.save_m2m()  # 保存关联多对多信息

    f. 用于更新和初始化

        obj = model.tb.objects.get(id=1)

        model_form_obj = XXOOModelForm(request.POST,instance=obj)

        ...

        PS: 单纯初始化

            model_form_obj = XXOOModelForm(initial={...})

ModelForm所有组件

所有组件

（1）自定义插件widgets

from django.forms import widgets as Fwidgets    #避免跟widgets重名

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        model = models.UserInfo     #去UserInfo类中获取数据

        fields = '__all__'        #__all__ 代指所有字段

        labels ={'username':'用户名'}

        help_texts = {'username':'...'}

        widgets = {

            'username':Fwidgets.Textarea(attrs={'class':'c1'})

        }

(2)错误信息error_message

from django.forms import widgets as Fwidgets    #避免跟widgets重名

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        ---snip---

        error_messages = {

            '__all__':{},       #整体的错误信息

            'email':{'required':'邮箱不能为空'}

        }

(3)自定义更改字段验证规则field_classses

from django.forms import fields as Ffields     #避免跟fields重名

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        ---snip---

        field_classes ={

            'email':Ffields.URLField    #把邮件格式改为url格式验证

        }

from django.shortcuts import render,redirect

from app01 import models

from django import forms

from django.forms import fields

from django.forms import widgets as Fwidgets

from django.forms import fields as Ffields     

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        model = models.UserInfo  # 去UserInfo类中获取数据

        fields = '__all__'  # __all__ 代指所有字段

        labels = {'username': '用户名'}

        help_texts = {'username': '...'}

        widgets = {

            'username': Fwidgets.Textarea(attrs={'class': 'c1'})

        }

        error_messages = {

            '__all__': {},  # 整体的错误信息

            'email': {'required': '邮箱不能为空'}

        }

        field_classes = {

            'email': Ffields.URLField  # 把邮件格式改为url格式验证

        }

def index(request):

    if request.method == 'GET':

        obj = UserInfoModelForm()

        return render(request,'index.html',{'obj':obj})

    elif request.method == 'POST':

        obj = UserInfoModelForm(request.POST)

        result = obj.is_valid()

        if result:

            print(obj.cleaned_data)             #如果models里没有__str__方法，则user_type获取

                                                        #到的是一个对象，可直接根据对象进行操作

            print(obj.cleaned_data['user_type'])

            # {'username': 'James', 'user_type': < UserType: 超级用户 >, 'email': 'ffd@fdsf.com'}

            # 超级用户

        else:

            print(obj.errors)

        return render(request,'index.html',{'obj':obj})

全部代码

3.ModelForm创建保存数据

from django.db import models

# Create your models here.

class UserInfo(models.Model):

    # verbose_name 等同于Form类里面的label

    username = models.CharField(verbose_name='用户',max_length=32)

    email = models.EmailField(verbose_name='邮件')

    user_type = models.ForeignKey(verbose_name='类型',to='UserType',to_field='id')

    user_group = models.ManyToManyField('UserGroup')

class UserType(models.Model):

    caption = models.CharField(max_length=32)

    def __str__(self):          #打印名称，不写显示的是obj对象

        return self.caption

class UserGroup(models.Model):

    groupname = models.CharField(max_length=32)

    def __str__(self):          #打印名称，不写显示的是obj对象

        return self.groupname

models

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>Title</title>

</head>

<body>

    <form action="/index/" method="post">

        {% csrf_token %}

        {{ obj.as_p }}

        <input type="submit" value="提交"/>

    </form>

</body>

</html>

index.html

from django import forms

from app import models

from django.forms import widgets as Fwidgets    #避免跟widgets重名

from django.forms import fields as Ffields     #避免跟fields重名

class UserInfoModelForm(forms.ModelForm):

    class Meta:

        model = models.UserInfo     #去UserInfo类中获取数据

        fields = '__all__'        #__all__ 代指所有字段

        labels ={'username':'用户名'}

        help_texts = {'username':'...'}

        widgets = {

            'username':Fwidgets.Textarea(attrs={'class':'c1'})

        }

        error_messages = {

            '__all__':{},       #整体的错误信息

            'email':{'required':'邮箱不能为空'}

        }

ModelForm验证

ModelForm验证

处理文件

from django.shortcuts import render

def index(request):

    if request.method == 'GET':

        obj = UserInfoModelForm()

        return render(request,'index.html',{'obj':obj})

    elif request.method == 'POST':

        obj = UserInfoModelForm(request.POST)

        if obj.is_valid():

            # 验证成功直接保存

            obj.save()         #默认commit=True，会保存多对多

            # 保存一对多表单

            # instance = obj.save(commit=False)

            # instance.save()

            # 保存多对多数据

            # obj.save_m2m()

        return render(request,'index.html',{'obj':obj})

4.ModelForm更新和初始化

描述：打开用户列表，显示用户信息，点击编辑跳转到编辑页面，Input显示选择用户的当前值；提交后，对数据进行更新

from django.conf.urls import url

from django.contrib import admin

from app01 import views

urlpatterns = [

    url(r'^admin/', admin.site.urls),

    url(r'^index/$', views.index),

    url(r'^list/$', views.user_list),

    url(r'^edit-(\d+)', views.user_edit),

]

url.py

from django.db import models

class UserInfo(models.Model):

    # verbose_name 等同于Form类里面的label

    username = models.CharField(verbose_name='用户',max_length=32)

    email = models.EmailField(verbose_name='邮件')

    user_type = models.ForeignKey(verbose_name='类型',to='UserType',to_field='id')

    user_group = models.ManyToManyField('UserGroup')

class UserType(models.Model):

    caption = models.CharField(max_length=32)

    def __str__(self):          #打印名称，不写显示的是obj对象

        return self.caption

class UserGroup(models.Model):

    groupname = models.CharField(max_length=32)

    def __str__(self):          #打印名称，不写显示的是obj对象

        return self.groupname

model.py

user_list.html

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>Title</title>

</head>

<body>

    <ul>

        {% for row in list %}

            <p>{{ row.username }}--{{ row.user_type.caption }}--<a href="/edit-{{ row.id }}">编辑</a></p>

        {% endfor %}

    </ul>

</body>

</html>

user_edit.html

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>Title</title>

</head>

<body>

    <form action="/edit-{{ nid }}" method="post">

        {% csrf_token %}

        {{ obj.as_p }}

        <input type="submit" value="提交" />

    </form>

</body>

</html>