javascript - Retrieve list of a specific attribute from a Backbone collection -


i'm looking way to, backbone collection, retrieve kind of array of 1 specific attribute. 

var somemodel = backbone.model.extend({     defaults: function() {         return {             attr1: "something",             attr2: "something",             attr3: "darkside"         };     } });  var somecollection = backbone.collection.extend({     model: somemodel,     url: '/data.json', });

now assume have above , want collection/array/similar attribute 'attr3'. there nice way (not manually iterating through somecollection , building new collection)? understanding underscore function "filter" returns entire somemodel based on premise, i.e. not want. ideas?

thanks

if want 1 attribute, can use _.pluck

somecollection.pluck('attr3');

for multiple attributes, can combine _.map on collections , _.pick on models

somecollection.map(function (model) {     return model.pick('attr2', 'attr3'); });

and demo http://jsfiddle.net/nikoshr/qpyxc/1/

or, more concise version using _.invoke

somecollection.invoke('pick', 'attr2', 'attr3');

http://jsfiddle.net/nikoshr/qpyxc/3/


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