DJANGO问题--Error: ‘ManyRelatedManager’ object is not iterableDjango: Error: ‘ManyRelatedManager’ object is not iterable

http://www.itblah.com/django-error-manyrelatedmanager-object-iterable/

while trying to iterate through a list of objects in a django template, i came across this error: “caught an exception while rendering: ‘manyrelatedmanager’ object is not iterable”

also of note is in the variables “<django.db.models.fields.related.manyrelatedmanager object at 0x9876545>” is returned rather than the value of that object.

to clarify, i’m trying to print a list of objects “items” associated with a model “things” through a manytomany relationship.

you may have guest,  but i’ve changed the actual model names to help protect my project.

class thing(models.model):

# comment

def __unicode__(self): # python 3: def __str__(self):

return self.name

name = models.charfield(max_length=32)

desc = models.charfield(max_length=254)

img = models.charfield(max_length=32)

items = models.manytomanyfield(measurement)

category = models.manytomanyfield(category)

if “my_things” exists, we’re going to create a list of all the objects it contains.

if the “my_things” object contains any “items”, these will be listed in a nested list.

well, thats the plan. in red i’ve highlighted the reasons it fails.

…

{% if my_things %}

<ul>

{% for thing in my_things %}

<li>{{ thing }}</li>

{% for item in things.items %}

<li>{{ thing.item }}</li>

{% endfor %}

</ul>

{% else %}

how to fix “‘manyrelatedmanager’ object is not iterable” error:

note the changes in red 

{% for item in things.items.all %}

<li>{{ item }}</li>