Django，访问父级'；多对一关系中的s域和方法

我下面的例子仅供演示，作者和书籍之间的关系是一对多的，每本书只能由一位作者撰写

假设我为作者创建了一个记录，然后创建了一本该作者写的书。当我想更新这本书的详细信息时，我也想获得作者的年龄，并获得对书籍模板中

作者

模型的任何字段的访问权限

{{form.author}

将返回作者姓名，我尝试了

{{form.author.age}

和

{form.author.find_age}

都没有成功

我的真实例子涉及一套书的形式，但我认为把它简单化为一本书，如下所示，将更容易得到答案

型号：

class Author(models.Model):
  name = models.CharField(max_length=300)
  age = models.DecimalField(max_digits=3, decimal_places=1, default=3.0, blank = True )

  def __str__(self):
    return self.name   

  def find_age(self):
    return self.age     

class Book(models.Model):
  author = models.ForeignKey(Author, on_delete=models.PROTECT)
  title = models.CharField(max_length=300)
  publish = models.CharField(max_length=300)

  def __str__(self):
    return self.title       

class BookCreate(CreateView):
   model = Book
   fields = '__all__'
   success_url = reverse_lazy('books-list')

class BookUpdate(UpdateView):
   model = Book
   success_url = reverse_lazy('books-list')
   fields = '__all__'    

class AuthorCreate(CreateView):
   model = Author
   fields = '__all__'
   success_url = reverse_lazy('authors-list')

class AuthorUpdate(UpdateView):
   model = Author
   success_url = reverse_lazy('authors-list')
   fields = '__all__'        

<div class="col-sm-3">
    {{form}}
</div>   

查看：

class Author(models.Model):
  name = models.CharField(max_length=300)
  age = models.DecimalField(max_digits=3, decimal_places=1, default=3.0, blank = True )

  def __str__(self):
    return self.name   

  def find_age(self):
    return self.age     

class Book(models.Model):
  author = models.ForeignKey(Author, on_delete=models.PROTECT)
  title = models.CharField(max_length=300)
  publish = models.CharField(max_length=300)

  def __str__(self):
    return self.title       

class BookCreate(CreateView):
   model = Book
   fields = '__all__'
   success_url = reverse_lazy('books-list')

class BookUpdate(UpdateView):
   model = Book
   success_url = reverse_lazy('books-list')
   fields = '__all__'    

class AuthorCreate(CreateView):
   model = Author
   fields = '__all__'
   success_url = reverse_lazy('authors-list')

class AuthorUpdate(UpdateView):
   model = Author
   success_url = reverse_lazy('authors-list')
   fields = '__all__'        

<div class="col-sm-3">
    {{form}}
</div>   

模板：

class Author(models.Model):
  name = models.CharField(max_length=300)
  age = models.DecimalField(max_digits=3, decimal_places=1, default=3.0, blank = True )

  def __str__(self):
    return self.name   

  def find_age(self):
    return self.age     

class Book(models.Model):
  author = models.ForeignKey(Author, on_delete=models.PROTECT)
  title = models.CharField(max_length=300)
  publish = models.CharField(max_length=300)

  def __str__(self):
    return self.title       

class BookCreate(CreateView):
   model = Book
   fields = '__all__'
   success_url = reverse_lazy('books-list')

class BookUpdate(UpdateView):
   model = Book
   success_url = reverse_lazy('books-list')
   fields = '__all__'    

class AuthorCreate(CreateView):
   model = Author
   fields = '__all__'
   success_url = reverse_lazy('authors-list')

class AuthorUpdate(UpdateView):
   model = Author
   success_url = reverse_lazy('authors-list')
   fields = '__all__'        

<div class="col-sm-3">
    {{form}}
</div>   

{{form}}

您可以使用

form.instance

{{form.instance.author.age}}

我因错过“实例”而损失了2天时间！！谢谢你，萨坦德拉。