在Django中，你如何将ForeignKey传递给Model的一个实例？ [英] In Django, how do you pass a ForeignKey into an instance of a Model?

问题描述

我正在写一个存储作业的应用程序。它们被定义为具有与用户链接的ForeignKey。我不明白在创建它时如何将ForeignKey传递给模型。我的工作模式没有外键，工作正常，但现在我试图添加用户到系统，我无法得到表单验证。

models.py ：django.db导入模型




从django导入表单
从django.contrib.auth导入
。模型导入用户

类Job（models.Model）：
user = models.ForeignKey（User）
name = models.CharField（max_length = 50，blank = True）
pub_date = models.DateTimeField（'date published'，auto_now_add = True）
orig_image = models.ImageField（'uploaded image'，upload_to ='origImageDB /'，blank = True）
clean_image = model.ImageField（'clean image'，upload_to ='cleanImageDB /'，blank = True）
fullsize_image = models.ImageField（'fullsize image'，upload_to ='fullsizeImageDB /'）
fullsize_clean_image = models。 ImageField（'fullsize clean image'，upload_to ='fullsizeCleanImageDB /'）
regions = models.TextField（blank = True）
orig_regions = models.TextField（blank = True）

类JobForm（forms.ModelForm）：
class Meta：
model = Job

在views.py中，我创建的对象如下：

  if request.method =='POST'：
 form = JobForm（request.POST，request.FILES）
如果form.is_valid（）：
 #Do这里的东西
  

我知道这会将表单数据和上传的文件传递给表单。但是，我不明白如何传入一个用户被设置为ForeignKey。

提前感谢任何可以帮助的人。

解决方案

Django中的一个典型模式是：

1. 用户字段从模型窗体


2. 将表单保存为 commit = False


3. 设置 job.user


4. 保存到数据库

在您的情况下：

 类JobForm（forms.ModelForm） ：
 class Meta：
 model = Job 
 exclude =（'user'，）
 
如果request.method =='POST'：
 form = JobForm（request.POST，request.FILES）
 job = form.save（commit = False）
 job.user = request.user 
 job.save（）
＃这里不需要下一行，因为我们没有任何m2m字段
 form.save_m2m（）
  

请参阅模型表单 save（）方法获取更多信息。

I am writing an application which stores "Jobs". They are defined as having a ForeignKey linked to a "User". I don't understand how to pass the ForeignKey into the model when creating it. My Model for Job worked fine without a ForeignKey, but now that I am trying to add users to the system I can't get the form to validate.

models.py:

from django.db import models
from django import forms
from django.contrib.auth.models import User

class Job(models.Model):
    user = models.ForeignKey(User)
    name = models.CharField(max_length=50, blank=True)
    pub_date = models.DateTimeField('date published', auto_now_add=True)
    orig_image = models.ImageField('uploaded image', upload_to='origImageDB/', blank=True)
    clean_image = models.ImageField('clean image', upload_to='cleanImageDB/', blank=True)
    fullsize_image = models.ImageField('fullsize image', upload_to='fullsizeImageDB/')
    fullsize_clean_image = models.ImageField('fullsize clean image', upload_to='fullsizeCleanImageDB/')
    regions = models.TextField(blank=True)
    orig_regions = models.TextField(blank=True)

class JobForm(forms.ModelForm):
    class Meta:
        model = Job

In views.py I was creating the objects as follows:

if request.method == 'POST':
    form = JobForm(request.POST, request.FILES)
    if form.is_valid():
        #Do something here

I understand that this passes the form data and the uploaded files to the form. However, I don't understand how to pass in a User to be set as the ForeignKey.

Thanks in advance to anyone who can help.

解决方案

A typical pattern in Django is:

1. exclude the user field from the model form
2. save the form with commit=False
3. set job.user
4. save to database

In your case:

class JobForm(forms.ModelForm):
    class Meta:
        model = Job
        exclude = ('user',)

if request.method == 'POST':
    form = JobForm(request.POST, request.FILES)
    job = form.save(commit=False)
    job.user = request.user
    job.save()
    # the next line isn't necessary here, because we don't have any m2m fields
    form.save_m2m()

See the Django docs on the model form save() method for more information.

这篇关于在Django中，你如何将ForeignKey传递给Model的一个实例？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！