Django管理员:添加& quot;删除文件& quot;图像或文件字段的字段 [英] Django admin: Add a "remove file" field for Image- or FileFields

问题描述

我在Internet上寻找一种轻松地允许用户清空在管理员中设置的imagefield/filefield的方法.

I was hunting around the Internet for a way to easily allow users to blank out imagefield/filefields they have set in the admin.

我发现了这一点: http://www.djangosnippets.org/snippets/894/.

这里真正令我感兴趣的是 rfugger 在评论中发布的代码:

What was really interesting to me here was the code posted in the comment by rfugger:

remove_the_file = forms.BooleanField(required=False)

def save(self, *args, **kwargs):
    object = super(self.__class__, self).save(*args, **kwargs)
    if self.cleaned_data.get('remove_the_file'):
        object.the_file = ''
    return object

当我尝试以自己的形式使用它时，我基本上将其添加到了已经有 BlahAdmin 的 admin.py 中.

When I try to use this in my own form I basically added this to my admin.py which already had a BlahAdmin.

class BlahModelForm(forms.ModelForm):
    class Meta:
        model = Blah

    remove_img01 = forms.BooleanField(required=False)

    def save(self, *args, **kwargs):
        object = super(self.__class__, self).save(*args, **kwargs)
        if self.cleaned_data.get('remove_img01'):
            object.img01 = ''
        return object

我运行它时收到错误消息

When I run it I get the error

调用Python对象时超出了最大递归深度

maximum recursion depth exceeded while calling a Python object

在此行:

object = super(self.__class__, self).save(*args, **kwargs)

当我仔细考虑一下时，很明显它只是无限地调用自身而导致错误.我的问题是我不知道应该怎么做.有什么建议吗?

When I think about it for a bit, it seems obvious that it is just infinitely calling itself causing the error. My problem is I can't figure out what is the correct way I should be doing this. Any suggestions?

根据要求提供的其他信息:

Additional information as requested:

blah 的型号:

Model of blah:

class Blah(models.Model):
    blah_name = models.CharField(max_length=25, unique=True)
    slug = models.SlugField()
    img01 = models.ImageField(upload_to='scenes/%Y/%m', blank=True)

    def __unicode__(self):
        return self.blah_name

推荐答案

请勿使用 super(self .__ class__，self)！请尝试以下示例:

Never use super(self.__class__, self)! Try the following example:

class A(object):
    def m(self):
        super(self.__class__, self).m()

class B(A): pass

B().m()

它将失败，并显示相同的错误:

It will fail with the same error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 4, in m
  ... repeated a lot of times ...
RuntimeError: maximum recursion depth exceeded while calling a Python object

让我们看看发生了什么.您为 B 实例调用 Am 方法，因此 self .__ class __ 是 B 和 super(self.__class __，self).m 指的是同一方法 Am ，因此 Am 会自行调用，而不是调用基类的方法.这导致无限递归.

Let's see what's going on. You call A.m method for B instance, so self.__class__ is B and super(self.__class__, self).m refers to the same method A.m, so A.m calls itself instead of calling the method of base class. This leads to infinite recursion.

这篇关于Django管理员:添加& quot;删除文件& quot;图像或文件字段的字段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！