def get_all_related_m2m_objects_with_model(self):
fields = self._get_fields(forward=False, reverse=True, include_hidden=True)
return [self._map_model(obj) for obj in fields if isinstance(obj.field, ManyToManyField)]
python类ManyToManyField()的实例源码
def model_to_dict(instance, fields=None, exclude=None):
"""
Returns a dict containing the data in ``instance`` suitable for passing as
a Form's ``initial`` keyword argument.
``fields`` is an optional list of field names. If provided, only the named
fields will be included in the returned dict.
``exclude`` is an optional list of field names. If provided, the named
fields will be excluded from the returned dict, even if they are listed in
the ``fields`` argument.
"""
# avoid a circular import
from django.db.models.fields.related import ManyToManyField
opts = instance._meta
data = {}
for f in chain(opts.concrete_fields, opts.virtual_fields, opts.many_to_many):
if not getattr(f, 'editable', False):
continue
if fields and f.name not in fields:
continue
if exclude and f.name in exclude:
continue
if isinstance(f, ManyToManyField):
# If the object doesn't have a primary key yet, just use an empty
# list for its m2m fields. Calling f.value_from_object will raise
# an exception.
if instance.pk is None:
data[f.name] = []
else:
# MultipleChoiceWidget needs a list of pks, not object instances.
qs = f.value_from_object(instance)
if qs._result_cache is not None:
data[f.name] = [item.pk for item in qs]
else:
data[f.name] = list(qs.values_list('pk', flat=True))
else:
data[f.name] = f.value_from_object(instance)
return data
def model_to_dict(instance, fields=None, exclude=None):
"""
Returns a dict containing the data in ``instance`` suitable for passing as
a Form's ``initial`` keyword argument.
``fields`` is an optional list of field names. If provided, only the named
fields will be included in the returned dict.
``exclude`` is an optional list of field names. If provided, the named
fields will be excluded from the returned dict, even if they are listed in
the ``fields`` argument.
"""
# avoid a circular import
from django.db.models.fields.related import ManyToManyField
opts = instance._meta
data = {}
for f in chain(opts.concrete_fields, opts.virtual_fields, opts.many_to_many):
if not getattr(f, 'editable', False):
continue
if fields and f.name not in fields:
continue
if exclude and f.name in exclude:
continue
if isinstance(f, ManyToManyField):
# If the object doesn't have a primary key yet, just use an empty
# list for its m2m fields. Calling f.value_from_object will raise
# an exception.
if instance.pk is None:
data[f.name] = []
else:
# MultipleChoiceWidget needs a list of pks, not object instances.
qs = f.value_from_object(instance)
if qs._result_cache is not None:
data[f.name] = [item.pk for item in qs]
else:
data[f.name] = list(qs.values_list('pk', flat=True))
else:
data[f.name] = f.value_from_object(instance)
return data
def model_to_dict(instance, fields=None, exclude=None):
"""
Returns a dict containing the data in ``instance`` suitable for passing as
a Form's ``initial`` keyword argument.
``fields`` is an optional list of field names. If provided, only the named
fields will be included in the returned dict.
``exclude`` is an optional list of field names. If provided, the named
fields will be excluded from the returned dict, even if they are listed in
the ``fields`` argument.
"""
# avoid a circular import
from django.db.models.fields.related import ManyToManyField
opts = instance._meta
data = {}
for f in chain(opts.concrete_fields, opts.virtual_fields, opts.many_to_many):
if not getattr(f, 'editable', False):
continue
if fields and f.name not in fields:
continue
if exclude and f.name in exclude:
continue
if isinstance(f, ManyToManyField):
# If the object doesn't have a primary key yet, just use an empty
# list for its m2m fields. Calling f.value_from_object will raise
# an exception.
if instance.pk is None:
data[f.name] = []
else:
# MultipleChoiceWidget needs a list of pks, not object instances.
qs = f.value_from_object(instance)
if qs._result_cache is not None:
data[f.name] = [item.pk for item in qs]
else:
data[f.name] = list(qs.values_list('pk', flat=True))
else:
data[f.name] = f.value_from_object(instance)
return data
def choices(self, cl):
from django.contrib.admin.views.main import EMPTY_CHANGELIST_VALUE
yield {
'selected': self.lookup_val is None and not self.lookup_val_isnull,
'query_string': cl.get_query_string({},
[self.lookup_kwarg, self.lookup_kwarg_isnull]),
'display': _('All'),
}
for pk_val, val in self.lookup_choices:
yield {
'selected': self.lookup_val == smart_text(pk_val),
'query_string': cl.get_query_string({
self.lookup_kwarg: pk_val,
}, [self.lookup_kwarg_isnull]),
'display': val,
}
if (isinstance(self.field, ForeignObjectRel) and
(self.field.field.null or isinstance(self.field.field, ManyToManyField)) or
hasattr(self.field, 'rel') and (self.field.null or isinstance(self.field, ManyToManyField))):
yield {
'selected': bool(self.lookup_val_isnull),
'query_string': cl.get_query_string({
self.lookup_kwarg_isnull: 'True',
}, [self.lookup_kwarg]),
'display': EMPTY_CHANGELIST_VALUE,
}
def get_all_related_many_to_many_objects(self, local_only=False):
include_parents = True if local_only is not True else PROXY_PARENTS
fields = self._get_fields(
forward=False, reverse=True,
include_parents=include_parents, include_hidden=True
)
return [obj for obj in fields if isinstance(obj.field, ManyToManyField)]
def get_all_related_m2m_objects_with_model(self):
fields = self._get_fields(forward=False, reverse=True, include_hidden=True)
return [self._map_model(obj) for obj in fields if isinstance(obj.field, ManyToManyField)]
