注意: 本章节会省略一些参数或方法的详细说明，因为在Form组件章节中提及到

ModelForm: 

• 通过 Model类（即: models.py 中的表类） 生成 form类（即: Form组件中所要创建的类）

• Form 组件有的，ModelForm 组件也有，Form 组件没有的，ModelForm 组件也有

• 不要认为用了ModelForm组件就一定要用它的自动渲染form表单功能，ModelForm组件只用于验证，不做form表单渲染也是可以的，因为最后都是从 request.POST 中获取数据进行验证，前提是 form表单中的 name 需要和 form类中的字段名一致

ModelForm 的校验:

• ModelForm 的校验是根据 Model类（即: models.py 中的表类）中的 字段 或 字段参数来判断传递过来的数据是否正确（和Form组件中的校验情况差不多，只不过Form组件是用Form类中的字段进行校验，而ModelForm是用Model类中的字段进行校验）

• 在 Model类（即: models.py 中的表类）中，EmailField、 URLField、 UUIDField 等字段只有在使用ModelForm的时候才有意义，因为这些字段是在使用ModelForm的时候验证传递过来的数据是否正确的时候使用的

1. 本章节所用到的表

# models.py

from django.db import models

class Book(models.Model):

    title = models.CharField(max_length=15)

    price = models.IntegerField()

    publish = models.ForeignKey(to='Publish')

    author = models.ManyToManyField(to='Author')

    def __str__(self):

        return self.title

    class Meta:

        verbose_name = "书籍"

        verbose_name_plural = verbose_name

class Publish(models.Model):

    title = models.CharField(max_length=15)

    def __str__(self):

        return self.title

    class Meta:

        verbose_name = '出版社'

        verbose_name_plural = verbose_name

class Author(models.Model):

    name = models.CharField(max_length=15)

    age = models.IntegerField()

    authorDetail = models.OneToOneField(to="AuthorDetail", on_delete=models.CASCADE, verbose_name='作者详情')  # 与AuthorDetail建立一对一的关系

    def __str__(self):

        return self.name

    class Meta:

        verbose_name = '作者'

        verbose_name_plural = verbose_name

class AuthorDetail(models.Model):

    birthday = models.DateField(verbose_name='生日')

    telephone = models.BigIntegerField(verbose_name='电话')

    addr = models.CharField(max_length=64, verbose_name='地址')

    def __str__(self):

        return str(self.telephone)

    class Meta:

        verbose_name = "作者详情表"

        verbose_name_plural = verbose_name

2. 创建 ModelForm

• 通过Model类，生成form类

# views.py 或 forms.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid  # 因为widgets和ModelForm中的参数重名了，所以起个别名

class BookForm(ModelForm):

    class Meta:

        model = Book  # 根据 Book 表类创建 Form 类

        fields = '__all__'  # 使用 Book 表类的所有字段，

# fields = ['title', 'price', 'publish', 'author']  # 使用 Book 表类的某几个字段

# exclude = ['publish', 'author']  # 排除某些字段，一般和 fields = '__all__' 搭配使用

        labels = {  # 和 Form 组件中的 label 作用是一样的

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  # 错误信息

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {  # 和 Form 组件中的 widgets作用是一样的

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.CheckboxSelectMultiple(attrs={'class': 'form-control'})

        }

3. 使用 ModelForm 渲染 Form 表单

• 和 Form 组件的使用方式是一样的

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid

class BookForm(ModelForm):

    class Meta:

        model = Book

        fields = '__all__'  

        labels = {

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {  

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.CheckboxSelectMultiple(attrs={'class': 'form-control'})

        }

def add_book(request):

book_form = BookForm()  # 实例化一个表单类

    return render(request, 'add.html', {'book_form': book_form})  # 将表单类传递给HTML模板，然后渲染出form表单

# add.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in book_form %}

        <div>

            {{ field.label }}

            {{ field }}

        </div>

    {% endfor %}

    <input type="submit">

</form>

4.使用 ModelForm 渲染 Form 表单，并且将对应数据自动填写到表单中（即: 修改页面）

• 通过Form组件渲染form表单，无法将对应数据自动填写到表单中（即：无法实现修改页面的自动填充数据效果），但是 ModelForm 可以实现

• instance 参数接收一个对象（即: 查询数据后得到的对象）

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid 

class BookForm(ModelForm):

    class Meta:

        model = Book

        fields = '__all__'  

        labels = {

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {  

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.CheckboxSelectMultiple(attrs={'class': 'form-control'})

        }

def edit_book(request, edit_book_id):

edit_book_obj = Book.objects.filter(pk=edit_book_id).first()  # 查询指定的book数据

    book_form = BookForm(instance=edit_book_obj)  # 将查询到的数据传递给 instance 参数，从而实现将对应数据自动填写到表单中（即: 修改页面）

    return render(request, 'add.html', {'book_form': book_form})

# edit.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in book_form %}

        <div>

            {{ field.label }}

            {{ field }}

        </div>

    {% endfor %}

    <input type="submit">

</form>

5. 自定义字段所输出的表单 HTML

# datetime_picker.html

<div class="input-group date form_date">

    <input readonly class="form-control"

           type="{{ widget.type }}"

           name="{{ widget.name }}"

            {% if widget.value != None %} value="{{ widget.value|stringformat:"s" }}" {% endif %}

            {% include "django/forms/widgets/attrs.html" %} />

    <span class="input-group-addon"><span class="glyphicon glyphicon-calendar"></span></span>

</div>

# widgets.py

from django import forms

class DateTimePickerInput(forms.TextInput):

    template_name = 'forms/widgets/datetime_picker.html'

# forms/coupon.py

from django.forms import ModelForm

from jyld_backstage.models import *

from django.forms import widgets as wid

from xadmin.forms.widgets import DateTimePickerInput

class CouponModelForm(ModelForm):

    class Meta:

        model = Coupon

        fields = '__all__'

        widgets = {

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'open_date': DateTimePickerInput,

        }

6. 获取 ModelForm 字段的相关信息

# views.py

from django.shortcuts import render

from app01.models import *

from django.forms import ModelForm

class UserInfoForm(ModelForm):

    class Meta:

        model = UserInfo

        fields = '__all__'

        labels = {

            'username': '用户名',

            'phone': '电话号码',

            'age': '年龄',

        }

def edit_data(request):

    user = UserInfo.objects.all().first()

    form = UserInfoForm(instance=user)

# 获取当前标签的相关信息

    # form['username'] 等同于 html 模板中循环出来的 field

    print(form['username'].__dict__)  # {'label': '用户名', 'name': 'username', ……}

# 获取当前标签属性的内容（如: class, id, value 等）

    for data in form['username']:

 # data 等同于 html 模板中循环出来的 field

        print(data.__dict__)  # {'data': {'required': True, 'type': 'text', 'name': 'username', 'template_name': 'django/forms/widgets/text.html', 'is_hidden': False, 'value': 'Amy', 'attrs': {'maxlength': '32', 'id': 'id_username', 'required': True'+'}'+'}'}}, ……}

    return render(request, 'change.html', {

        'form': form

    })

# xxx.html

<form method="post" novalidate>

    {% csrf_token %}

    {% for field in form %}

        <p>

            {{ field.label }}：

            <input

                    type="{{'{'+'{'+' field.0.data.type '+'}'+'}'}}"

                    value="{{'{'+'{'+' field.0.data.value '+'}'+'}'}}"

                    id="{{'{'+'{'+' field.0.data.attrs.id '+'}'+'}'}}"

                    maxlength="{{'{'+'{'+' field.0.data.attrs.maxlength '+'}'+'}'}}"

                    name="{{ field.name }}"

            >

        </p>

    {% endfor %}

    <input type="submit" value="提交">

</form>

7. 添加数据

• 直接通过 ModelForm 中的 .save() 方法将提交过来的数据添加到数据库中，如果是使用 form 组件就需要自己写 orm 语句将提交过来的数据添加数据库中

• .save() 方法的返回值就是所添加的该条数据对象

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid

class BookForm(ModelForm):

    class Meta:

        model = Book  

        fields = '__all__'  

        labels = {  

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.CheckboxSelectMultiple(attrs={'class': 'form-control'})

        }

def add_book(request):

    if request.method == 'POST':

        book_form = BookForm(request.POST)

        if book_form.is_valid():

            book_data = book_form.save() # 将提交过来的数据保存到数据库

print(book_data.pk, book_data.title)  # 10 三国演义

            return redirect('/books/')

        else:

            print(book_form.errors)

            return HttpResponse('添加失败')

    book_form = BookForm()

    return render(request, 'add.html', {'book_form': book_form})

# add.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in book_form %}

        <div>

            {{ field.label }}

            {{ field }}

        </div>

    {% endfor %}

    <input type="submit">

</form>

8. 修改数据

• 直接通过 ModelForm 中的 instance 参数修改数据库中的数据，如果是使用 form 组件就需要自己写 orm 语句修改数据库中的数据

• instance 参数接收一个对象（即: 查询数据后得到的对象）

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid

class BookForm(ModelForm):

    class Meta:

        model = Book  

        fields = '__all__'  

        labels = {  

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.CheckboxSelectMultiple(attrs={'class': 'form-control'})

        }

def edit_book(request, edit_book_id):

edit_book_obj = Book.objects.filter(pk=edit_book_id).first()

    if request.method == 'POST':

        book_form = BookForm(request.POST, instance=edit_book_obj)  # 验证提交过来的数据是否有误，并且通过 instance 参数指定要修改那条数据

                                                                    # 如果没有指定 instance 参数那么在执行 .save() 方法的时候该操作就是新增数据的操作

                                                                    # 不要和下面的 instance 参数搞混了，虽然 instance 参数的作用是一样的，但是表达的意思是不一样的

                                                                    #（即：下面instance参数表达的是将对应数据自动填写到表单中，而这里表达的是指定要修改那条数据）

        if book_form.is_valid():

            book_data = book_form.save()

            print(book_data.pk, book_data.title)  # 10 三国演义2 

            return redirect('/books/')

        else:

            return HttpResponse('修改失败')

    book_form = BookForm(instance=edit_book_obj)  # 将查询到的数据传递给 instance 参数，从而实现将对应数据自动填写到表单中（即: 修改页面） 

    return render(request, 'add.html', {'book_form': book_form})

# edit.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in book_form %}

        <div>

            {{ field.label }}

            {{ field }}

        </div>

    {% endfor %}

    <input type="submit">

</form>

9. 自定义字段

• 注意: 

• 定义自定义字段的方法和 form 组件定义字段的方法是一样的

• 自定义字段的字段名不能和 ModelForm 中所指向的 表类（即: Model类）中的字段名重复

• 因为如果自定义字段的字段名和当前 ModelForm 所指向的 表类（即: Model类）中的字段名一样，那么该自定义字段就是 表类（即: Model类）的字段而不是自定义字段

• 使用方式一 -> 确认密码

# forms/password.py

from django.forms import ModelForm

from django.forms import widgets as wid

from django.forms import fields as Ffields

from django.core.exceptions import ValidationError

from .models import *

class RegForm(ModelForm):

confirm_password = Ffields.CharField(

        min_length=6,

        label='确认密码',

        widget=wid.PasswordInput(

            attrs={

                'class': 'form-control',

                'placeholder': '确认密码',

            }

        ),

        error_messages={

            'required': '确认密码不能为空',

            'min_length': '确认密码不能小于6位',

        }

    )

    class Meta:

        model = UserInFo

        fields = ['password', 'confirm_password']

        labels = {

            'password': '密码',

        }

        error_messages = {

            'password': {'required': '密码不能为空', 'min_length': '密码不能小于6位', },

        }

        widgets = {

            'password': wid.PasswordInput(attrs={'class': 'form-control', 'placeholder': '密码'}),

        }

# 重写全局钩子，判断两次密码是否一致

    def clean(self):

        password = self.cleaned_data.get('password')

        confirm_password = self.cleaned_data.get('confirm_password')

        if password == confirm_password:

            return self.cleaned_data

        else:

            self.add_error('confirm_password', ValidationError('两次密码不一致'))

• 使用方式二 -> 添加当前表的一对一字段所关联表的内容到当前 form 表单中

• 自定义字段一般用于当前表类拥有一对一字段，且一对多或多对多很少会用到

• ModelForm 源码中两个重要属性:

• self.instance -> 字段对象
• self.initial -> 初始值（即: 修改页面所显示的每个字段所对应的数据）

# forms/author.py

from django import forms

from django.forms import ModelForm

from app01.models import *

class BootStrapModelForm(ModelForm):

    def __init__(self, *args, **kwargs):

        super().__init__(*args, **kwargs)  # 调用父类的 __init__ 方法

# 批量添加样式

        for field in iter(self.fields):

            self.fields[field].widget.attrs.update({

                'class': 'form-control'

            })

class AuthorForm(BootStrapModelForm):

# 自定义字段

birthday = forms.DateField(label='出生日期')

telephone = forms.IntegerField(label='手机号码')

addr = forms.CharField(label='地址')

    class Meta:

        model = Author

        fields = ['name', 'age']

        labels = {

            'name': '作者名称',

            'age': '年龄',

        }

        error_messages = {

            'name': {'required': "作者名称不能为空"},

            'age': {'required': "年龄不能为空"},

            'birthday': {'required': "出生日期不能为空"},

            'telephone': {'required': "手机号码不能为空"},

            'addr': {'required': "地址不能为空"},

        }

# 重写 ModelForm 的 __init__ 方法

    def __init__(self, *args, **kwargs):

        super().__init__(*args, **kwargs)  # 调用父类的 __init__ 方法

# self.instance -> 字段对象

        # self.initial -> 初始值（即: 修改页面所显示的每个字段所对应的数据）

# 修改数据时所显示的自定义字段的对应数据

        if self.instance.authorDetail_id:  # 使用字段对象下的 一对一 或 多对多 字段属性进行判断

            self.initial['birthday'] = self.instance.authorDetail.birthday

            self.initial['telephone'] = self.instance.authorDetail.telephone

            self.initial['addr'] = self.instance.authorDetail.addr

# 重写 ModelForm 的 save 方法

    def save(self, commit=True):

 # self.instance -> 字段对象

        # self.initial -> 初始值（即: 修改页面所显示的每个字段所对应的数据）

# 注意: 必须将修改数据的判断放到添加数据的判断前面

# 修改数据时自定义字段数据的保存

        if self.instance.authorDetail_id:  # 使用字段对象下的 一对一 或 多对多 字段属性进行判断

            authordetail_queryset = AuthorDetail.objects.filter(pk=self.instance.authorDetail_id).all()

            authordetail_queryset.update(

                birthday=self.cleaned_data['birthday'],

                telephone=self.cleaned_data['telephone'],

                addr=self.cleaned_data['addr'],

            )

 # 该判断中所执行的内容，只适用于当前 Model 表中有 一对一、一对多、多对多字段

        # 新建数据时自定义字段数据的保存

        if not self.instance.authorDetail_id:  # 使用字段对象下的 一对一 或 多对多 字段属性进行判断

# 新建数据时先新建 外键字段 或 一对一字段 的数据

            author_detail_obj = AuthorDetail.objects.create(

                birthday=self.cleaned_data['birthday'],

                telephone=self.cleaned_data['telephone'],

                addr=self.cleaned_data['addr']

            )

# 将新建好的数据 id 赋值给当前字段对象的指定 外键字段 或 一对一字段 上

            self.instance.authorDetail_id = author_detail_obj.pk

        super().save(commit=True)  # 调用父类 ModelForm 的 save 保存方法

        return self.instance  # 一定要返回 self.instance

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from app01.forms.author import AuthorForm

def add_author(request):

    author_form = AuthorForm()

    if request.method == 'POST':

        author_form = AuthorForm(request.POST)

        if author_form.is_valid():

            author_form.save()

            return redirect('/authors/')

    return render(request, 'change.html', {'form': author_form})

def edit_author(request, edit_author_id):

    edit_author_obj = Author.objects.filter(pk=edit_author_id).first()

    author_form = AuthorForm(instance=edit_author_obj)

    if request.method == 'POST':

        author_form = AuthorForm(request.POST, instance=edit_author_obj)

        if author_form.is_valid():

            author_form.save()

            return redirect('/authors/')

    return render(request, 'change.html', {'form': author_form})

# change.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in form %}

        <div class="form-group {% if field.errors %} has-error {% endif %}">

            {{ field.label }}

            {{ field }}

            <span class="help-block">{{ field.errors.0 }}</span>

        </div>

    {% endfor %}

    <input type="submit" class="btn btn-success">

</form>

10. 保存或修改上传文件

# forms/picture.py

from django.forms import ModelForm

from app01.models import *

from django.forms import widgets as wid

class PictureForm(ModelForm):

    class Meta:

        model = Picture

        fields = '__all__'

        labels = {

            'title': '标题',

            'img': '图片',

        }

        error_messages = {

            'title': {'required': "标题不能为空"},

            'img': {'required': "图片不能为空"},

        }

        widgets = {

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'img': wid.FileInput(attrs={'class': 'form-control'}),

        }

# views.py

from app01.models import *

from django.shortcuts import render, HttpResponse

from app01.forms.picture import PictureForm

def add_data(request):

    picture_form = PictureForm()

    if request.POST:

        picture_form = PictureForm(request.POST, request.FILES)

        if picture_form.is_valid():

            picture_form.save()

            return HttpResponse('添加成功')

    return render(request, 'change.html', {

        'form': picture_form,

    })

def edit_data(request, edit_pk):

    picture_obj = Picture.objects.filter(pk=edit_pk).first()

    picture_form = PictureForm(instance=picture_obj)

    if request.POST:

        picture_form = PictureForm(request.POST, request.FILES, instance=picture_obj)

        if picture_form.is_valid():

            picture_form.save()

            return HttpResponse('修改成功')

    return render(request, 'change.html', {

        'form': picture_form,

    })

# change.html

<form method="post" enctype="multipart/form-data" novalidate>

    {% csrf_token %}

    {% for field in form %}

        <div>

            {{ field.label }}

            {{ field }}

        </div>

        <p>{{ field.errors.0 }}</p>

    {% endfor %}

    <input type="submit" value="提交">

</form>

11. .queryset.model ->  获取该字段对象下所关联的模型表（即: 表类）

• 获取form的字段对象方法在Form组件章节中有提到

• .queryset 只作用于 一对一、一对多、多对多字段

• 语法: 字段对象.queryset.model

# views.py 或 forms.py

from django.forms import ModelForm

class BookForm(ModelForm):

    class Meta:

        model = Book

        fields = '__all__'

book_form_obj = BookForm()

# 获取 一对多 的字段对象

field_obj = book_form_obj.fields['publish']  # <django.forms.models.ModelChoiceField object at 0x000001F2AC79E7B8>

# 获取该字段对象下所关联的模型表

model = field_obj.queryset.model  # <class 'app01.models.Publish'>

# 获取该模型表下的数据

model_data = model.objects.all()  # <QuerySet [<Publish: 东莞出版社>, <Publish: 广州出版社>]>

# 获取该模型表所在的app名称

app_label = model._meta.app_label  # app01

# 获取该模型表的表名

model_name = model._meta.model_name  # publish

12. 只用 ModelFo组件 进行验证，不做渲染

• 不要认为用了ModelForm组件就一定要用它的自动渲染form表单功能，ModelForm组件只用于验证，不做form表单渲染也是可以的，因为最后都是从 request.POST 中获取数据进行验证，前提是 form表单中的 name 需要和 form类中的字段名一致

• 只用ModelForm组件进行验证，不做渲染（即: 自己编写form表单） -> 使用 form 表单提交数据

# 这里就不写例子了，因为和form组件章节中的列子差不多

13. 图书管理例子

# models.py

from django.db import models

class Book(models.Model):

    title = models.CharField(max_length=15)

    price = models.IntegerField()

    publish = models.ForeignKey(to='Publish')

    author = models.ManyToManyField(to='Author')

    def __str__(self):

        return self.title

    class Meta:

        verbose_name = "书籍"

        verbose_name_plural = verbose_name

class Publish(models.Model):

    title = models.CharField(max_length=15)

    def __str__(self):

        return self.title

    class Meta:

        verbose_name = '出版社'

        verbose_name_plural = verbose_name

class Author(models.Model):

    name = models.CharField(max_length=15)

    def __str__(self):

        return self.name

    class Meta:

        verbose_name = '作者'

        verbose_name_plural = verbose_name

# views.py

from django.shortcuts import render, HttpResponse, redirect

from .models import *

from django.forms import ModelForm

from django.forms import widgets as wid  # 因为widgets和ModelForm中的参数重名了，所以起个别名

class BookForm(ModelForm):

    class Meta:

        model = Book  # 根据 Book 表类创建 Form 类

        fields = '__all__'  # 使用 Book 表类的所有字段，

        # fields = ['title', 'price', 'publish', 'author']  # 使用 Book 表类的某几个字段

        # exclude = ['publish', 'author']  # 排除某些字段，一般和 fields = '__all__' 搭配使用

        labels = {  # 和 Form 组件中的 label 作用是一样的

            'title': '书籍名称',

            'price': '价格',

            'publish': '出版社',

            'author': '作者'

        }

        error_messages = {  # 错误信息

            'title': {'required': "书籍名称不能为空"},

            'price': {'required': "价格不能为空"},

            'publish': {'required': "请选择出版社"},

            'author': {'required': "请选择作者"},

        }

        widgets = {  # 和 Form 组件中的 widgets作用是一样的

            'title': wid.TextInput(attrs={'class': 'form-control'}),

            'price': wid.TextInput(attrs={'class': 'form-control'}),

            'publish': wid.Select(attrs={'class': 'form-control'}),

            'author': wid.SelectMultiple(attrs={'class': 'form-control'})

        }

def books(request):

    book_list = Book.objects.all()

    return render(request, 'books.html', {'book_list': book_list})

def add_book(request):

    book_form = BookForm()

    if request.method == 'POST':

        book_form = BookForm(request.POST)

        if book_form.is_valid():

            book_form.save()  # 将提交过来的数据保存到数据库

            return redirect('/books/')

    return render(request, 'add.html', {'book_form': book_form})

def edit_book(request, edit_book_id):

    edit_book_obj = Book.objects.filter(pk=edit_book_id).first()

    book_form = BookForm(instance=edit_book_obj)

    if request.method == 'POST':

        book_form = BookForm(request.POST, instance=edit_book_obj)  # 验证提交过来的数据是否有误，并且通过 instance 参数指定要修改那条数据

                                                                    # 如果没有指定 instance 参数那么在执行 .save() 方法的时候该操作就是新增数据的操作

                                                                    # 不要和上面的 instance 参数搞混了，虽然 instance 参数的作用是一样的，但是表达的意思是不一样的

                                                                    #（即：上面instance参数表达的是将对应数据自动填写到表单中，而这里表达的是指定要修改那条数据）

        if book_form.is_valid():

            book_form.save()

            return redirect('/books/')

    return render(request, 'edit.html', {'book_form': book_form})

# urls.py

from django.conf.urls import url

from django.contrib import admin

from app01 import views

urlpatterns = [

    url(r'^admin/', admin.site.urls),

    url(r'^books', views.books),

    url(r'^add_book', views.add_book),

    url(r'^edit_book/(\d+)', views.edit_book),

 # url(r'^delete_book', views.delete_book),

]

# books.html

<!DOCTYPE html>

<html>

<head>

    <meta charset="utf-8">

    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

    <title>Title</title>

    <meta name="description" content="">

    <meta name="keywords" content="">

    <link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">

</head>

<body>

<div class="container">

    <a href="/add_book/" class="btn btn-info">添加书籍</a>

    <table border="1" class="table table-bordered">

        <thead>

        <tr>

            <th>id</th>

            <th>书名</th>

            <th>价格</th>

            <th>出版社</th>

            <th>作者</th>

            <th>操作</th>

        </tr>

        </thead>

        <tbody>

        {% for book in book_list %}

            <tr>

                <td>{{ book.pk }}</td>

                <td>{{ book.title }}</td>

                <td>{{ book.price }}</td>

                <td>{{ book.publish.title }}</td>

                <td>

                    {% for author in book.author.all %}

                        {{ author.name }}

                    {% endfor %}

                </td>

                <td>

                    <a href="/edit_book/{{ book.pk }}">编辑</a>

{% comment %}<a href="/delete_book/{{ book.pk }}">删除</a>{% endcomment %}

                </td>

            </tr>

        {% endfor %}

        </tbody>

    </table>

</div>

<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>

<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>

</body>

</html>

# form.html

<form action="" method="post" novalidate>

    {% csrf_token %}

    {% for field in book_form %}

        <div class="form-group {% if field.errors %} has-error {% endif %}">

            {{ field.label }}

            {{ field }}

            <span class="help-block">{{ field.errors.0 }}</span>

        </div>

    {% endfor %}

    <input type="submit" class="btn btn-success">

</form>

# add.html

<!DOCTYPE html>

<html>

<head>

    <meta charset="utf-8">

    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

    <title>Title</title>

    <meta name="description" content="">

    <meta name="keywords" content="">

    <link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">

</head>

<body>

<div class="container">

    <h3>添加页面</h3>

    {% include 'form.html' %}

</div>

<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>

<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>

</body>

</html>

# edit.html

<!DOCTYPE html>

<html>

<head>

    <meta charset="utf-8">

    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

    <title>Title</title>

    <meta name="description" content="">

    <meta name="keywords" content="">

    <link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">

</head>

<body>

<div class="container">

    <h3>修改页面</h3>

    {% include 'form.html' %}

</div>

<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>

<script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.min.js"></script>

</body>

</html>