backbone js getByCid not working

Question

The backbone getByCid is not working when i viewed in console.log it showing the error as TypeError: test.getByCid is not a function. By using at(0).cid it shows the output as 'c1' why its not working.

var test=new Backbone.Collection([ 
   {name:'gowtham',age:10}
]);
console.log(test.at(0).cid); // output as c1
console.log(JSON.stringify(test.getByCid('c1'))); //TypeError: test.getByCid is not a function

Answer 1

the Backbone.Collection does not have method getByCid, thats why you are getting this error.
But a collection has get method for getting a model.
it accepts one argument: model | id | cid

So if you want to get a model by cid, you can do it like this collection.get(cidValue)

let collection = new Backbone.Collection();
let test1 = new Backbone.Model({ id: 1, value: 'first' });
let test2 = new Backbone.Model({ id: 2, value: 'second' });

collection.add([test1, test2]);

console.log(collection.get(2));
// find test2 by id

console.log(collection.get('c2'));
// find test2 by cid

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