如何有条件地使用django多表继承保存表单 [英] how to conditionally save a form using django multi table inheritance

问题描述

我有以下形式：

class PlaceForm（forms.ModelForm）：

class PlaceForm(forms.ModelForm):

class Meta:        
    model = Place

我有以下模型：

class Place(models.Model):
    customer = models.ForeignKey(Customer)
    name = models.CharField(max_length=50)
    address = models.CharField(max_length=80)

class Restaurant(Place):
    serves_hot_dogs = models.BooleanField()
    serves_pizza = models.BooleanField()

在我看来，我想有条件地保存一个地方或一个餐厅取决于传入的网址。

In my view I want to conditionally save either a Place or a Restaurant depending on the incoming url.

我尝试了以下内容：

if form.is_valid():
                place = form.save(commit=False)
                place.customer = customer
                place.save()

                if url_name == 'restaurant':
                     restaurant = Restaurant(place_ptr_id=place.id)
                     restaurant.save()

一个地方从表单，然后尝试创建餐厅，但失败与以下：（1048，列'customer_id'不能为空）

This creates a place from the form and then tries to create a restaurant, but fails with following: (1048, "Column 'customer_id' cannot be null")

这是告诉我新的一个地方试图插入餐厅排。

This is telling me that a new row for a new place is trying to be inserted and then the restaurant row.

我看到一个几个不同的选项：

I see a few different options:

1. 将该地方转换为餐厅，并将其另存为转换对象。


2. 有条件地将表单的模型类型更改为Place或Restaurant

如何有条件地保存不同的父项和子对象？

How can I accomplish saving the different parent and child objects conditionally?

推荐答案

与 Django模型继承：crea现在的实例（downcast）的子实例？，它建议如何使用现有的基类对象添加对象。

It is related to Django model inheritance: create sub-instance of existing instance (downcast)? which suggests how to add object with existing base class object.

你可能想看看我的问题：派生模型文件夹不可用

You may want to look at my question: Derived model filefield not available

简单来说，您要做的是

restaurant = Restaurant(place_ptr_id=place.id)
restaurant.__dict__.update(place.__dict__)
restaurant.save()

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