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Django更新整个对象(行)

django python

Pranav S · 技术社区 · 6 年前

我试图用username和fullname属性更新一个名为User的对象;我的模型在下面。

class User(models.Model):
"""docstring for User"""

fullname = models.TextField()
username = models.TextField()
password = models.TextField()
createdDate = models.DateTimeField(default=timezone.now)
publishedDate = models.DateTimeField(blank=True, null=True)

def publish(self):
    self.publishedDate = timezone.now
    self.save()

def __str__(self):
    return str("\npk= " + self.pk + " | fullname= " + self.fullname + " | username= " + self.username + "\n")

我已经创建了一个编辑页面,可以通过request.POST[“fullname”]和request.POST[“username”]在我的视图中获取该页面的值。

我的问题是如何更新整个对象而不必在update中指定特定的属性,或者不获取对象并设置新值并保存对象;我的观点如下。

def editUserByID(request, userID):
    if (request.method == "POST"):
        if (request.POST["userID"] != '' and request.POST["fullname"] != '' and request.POST["username"] != ''):
            user1 = User(
                pk=request.POST["userID"],
                fullname=request.POST["fullname"],
                username=request.POST["username"]
            )

        print(user1)

        # this only updates 1 property, so for multiple properties I would have to write multiple statements
        User.objects.filter(pk=user1.pk).update(fullname=user1.fullname) 

        # is this possible? send the entire object and have it update the DB
        User.objects.filter(pk=user1.pk).update(user1)  

        # this is how I was able to save it, but have to get the existing object again, assign the new values and then save
        updateUser = User.objects.get(pk=user1.pk)
        updateUser.fullname=user1.fullname
        updateUser.username=user1.username
        updateUser.save()

else:
    user2 = User.objects.get(pk=userID)
    return render (request, 'helloworld/editUser.html', {'user': user2})
return redirect('listUsers')

2 回复 | 直到 6 年前

Daniel Roseman 6 年前

这基本上是错误的做法。首先,不需要创建 user1 ; 如果要更新现有对象,应该直接在那里设置值。

但是在Django中实现这一点的方法是使用一个ModelForm。这有很多优点,特别是它将验证您的输入,检查是否提供了所有必需的字段,以及这些字段的类型是否正确。以现有用户的身份传递 instance 参数,然后当您保存它时,该实例将被更新。

class UserForm(forms.ModelForm):
    class Meta:
        model = User
        fields = '__all__'

...

def editUserByID(request, userID):
    obj = User.objects.get(userID)
    if request.method == 'POST':
        form = UserForm(request.POST, instance=obj)
        if form.is_valid():
           form.save() # updates the existing object
           return redirect('home')
    else:
        form = UserForm(instance=obj)  #  prepopulates the form with values from the instance
    return render(request, 'mytemplate.html', {'form': form})

Usman Abasi 6 年前

你可以这样做:

User.objects.filter(pk=user1.pk).update(fullname=user1.fullname, 
username=user1.username)

另一种更新模型的方法是使用如下表单:

# You can get user based on your logic
user = request.user
# 'EditUserForm' is the custom form, read more about django model forms if you already have not, https://docs.djangoproject.com/en/2.1/topics/forms/modelforms/#the-save-method
user_form = EditUserForm(request.POST, instance=user)
if user_form.is_valid():
    user_form.save()
else:
    user2 = User.objects.get(pk=userID)
    return render (request, 'helloworld/editUser.html', {'user': user2})

return redirect('listUsers')