javascript - how to override Backbone's parse function? - Stack Overflow

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I try to use backbone in my project. But I have met problem when try to overide parse method of Backbone. The server has send back more data than I want.For example: What I want is:

[{
   id: "123",
   name: "david"
},{
   id: "456",
   name: "kevin"
}]

but the server's result is :

{
 total: 1000,
 items:[{
   id: "123",
   name: "david"
},{
   id: "456",
   name: "kevin"
}]
}

so I want process result in parse method and return only the array. How can I do this? When I try I got error. How should I do?

I try to use backbone in my project. But I have met problem when try to overide parse method of Backbone. The server has send back more data than I want.For example: What I want is:

[{
   id: "123",
   name: "david"
},{
   id: "456",
   name: "kevin"
}]

but the server's result is :

{
 total: 1000,
 items:[{
   id: "123",
   name: "david"
},{
   id: "456",
   name: "kevin"
}]
}

so I want process result in parse method and return only the array. How can I do this? When I try I got error. How should I do?

• javascript
• backbone.js

Share Improve this question Follow edited Aug 20, 2012 at 18:29 Rostyslav Dzinko 40.8k55 gold badges5353 silver badges6565 bronze badges asked Aug 20, 2012 at 12:49 user1611764user1611764 1111 silver badge22 bronze badges 2

• How do you expect us to help you fix the code if you don't post any code? – asawyer Commented Aug 20, 2012 at 12:51
• What did you try so far? – Richard Ev Commented Aug 20, 2012 at 13:03

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2 Answers 2

Sorted by: Reset to default 7

In your backbone model, define the parse function the way you would like:

Model = Backbone.Model.extend({
    parse: function () {
        return {
            id: this.get("id"),
            name: this.get("name")
        }
    }
});

But, it would be better to handle and set the data in the model initializer, like so:

Model = Backbone.Model.extend({
    initialize: function (attrs) {
        try {
            //TODO HERE: test for correct values and throw errors

            // set object variables here
            this.set({
                name: attrs.name,
                id: attrs.id
            });

        } catch (e) {
            console.log(e);
        }
    }
});

No need to overwrite the parse function now. This way you know the data that your model is handling is good, and you set what variables it contains. This avoids many errors from invalid data.

Each item in the array should really be a submodel, which is what I have written above. Your parent model should look like:

Model = Backbone.Model.extend({
    initialize: function (items) {
        this.subModels = [];
        items.forEach(function (item) {
            this.subModels.push( new SubModel(item) )
        });
    }
});

Or as a collection:

Collection = Backbone.Collection.extend({
    model: ItemModel,
});

To which you would pass response.items

From Backbone Parse docs

Collection = Backbone.Collection.extend({
    model: YourModel,
    parse: function(response){
        return response.items;
    }
});

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