Question

I’ve got a backbone collection and I’m trying to filter by an id within the attributes
basically, a user has classes, and the class has a location_id, and I want to filter by the location id. My collection looks like this to give you an idea.

-user
   -models
     -0
       -attributes
         -location_id
      -1
       -attributes
         -location_id
      -2
       -attributes
         -location_id

I thought I could filter this by using

  var get_locations = user_class_collection.filter(function(classes){
      console.log(classes); 
       return classes.get(location_id)==location.id;
       });

  console.log(get_locations);

but that is returning an empty array, when I know the location_id is in the collection.
Any idea why this isn’t working? I’ve also tried to grab classes.attributes.get, but it wasn’t any better

In the first few responses, it was properly mentioned that I had to quote the get('location_id'). I’ve now done that, but unfortunately, I’m still getting an empty array. I thought that the filter would loop through the classes and I would get a console output for each class, but the console.log(classes) is only getting triggered once. Is that a hint? Or a red-herring?

Answer 1

you are trying to get a property from classes that is named as the value of the location_id parameter
you should instead make that a string (in fact you can choose how you make it a string, single or double quotes both work)

user_class_collection.filter(function(classes){
    return classes.get('location_id') == location.id;
});