Added value_from_object method to db Field class

git-svn-id: http://code.djangoproject.com/svn/django/trunk@4252 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/fields/__init__.py

@@ -339,6 +339,10 @@ class Field(object):
         # TODO: This is just a temporary default during development.
         return forms.CharField(required=not self.blank, label=capfirst(self.verbose_name), initial=initial)
 
+    def value_from_object(self, obj):
+        "Returns the value of this field in the given model instance."
+        return getattr(obj, self.attname)
+
 class AutoField(Field):
     empty_strings_allowed = False
     def __init__(self, *args, **kwargs):

django/db/models/fields/related.py

@@ -721,6 +721,10 @@ class ManyToManyField(RelatedField, Field):
     def set_attributes_from_rel(self):
         pass
 
+    def value_from_object(self, obj):
+        "Returns the value of this field in the given model instance."
+        return getattr(obj, self.attname).all()
+
     def formfield(self, initial=None):
         return forms.MultipleChoiceField(choices=self.get_choices_default(), required=not self.blank, label=capfirst(self.verbose_name), initial=initial)