#django what method is used to represent a model field in admin

I开发者_开发百科 am trying to subclass CharField with a custom unicode method. Basically, I want to be able to call my custom crypto method on the value that is returned by the default model field. I tried the following, but it seems that admin is getting the values some other way. It seems to me that this would be the most pythonic way to implement this, but perhaps I'm wrong.

def PasswordCharField(models.CharField):  
    def __unicode__(self):  
        return crypt(super(PasswordCharField,self).__unicode__())

I'm still not really sure why you're trying to encrypt a field on output - that doesn't seem very secure, the usual approach (taken by Django's own password fields) is to hash the data on entry and store that hashed version on the database.

However, if you want to go down this route, there's still no reason to use __unicode__ on a custom field subclass. There's nothing in the documentation that implies that this is what any part of Django - whether the admin or anything else - uses to get the value of a field. In fact, the admin uses exactly the same method to get the value of a field as anything else.

Custom field subclasses are fully described in the documentation, linked from the contents page. Without really understanding what you're trying to do it's hard to tell, but it could be that the to_python method is what you need. Bear in mind though that this will affect the value of the field for all uses in Django.