Question

How can I add a composed default value to a charfield?

Example

class Myclass(xxx):

type = models.ForeignKey(somewhere)
code = models.CharField(default=("current id of MyClass wich is autoincremented + type value"))

Is it possible?

Answer 1

To do so, you override the save method on your model.

class MyClass(models.Model):
    ...

    def save(self):
        super(Myclass,self).save()
        if not self.code:
            self.code = str(self.id) + str(self.type_id)
            self.save()

There is stuff you need to take care, like making the code a blank field, but you get the idea.