Backbone: Create collection from JSON

问题:

I'm attempting to load JSON (from php's json_encode) into a Backbone JS collection. I've simplified the problem to:

var myJSON = '[{ "id":"1","name":"some name","description":"hmmm"}]';

var myCollection = new MyCollection(myJSON, { view: this });

And:

MyObject = Backbone.Model.extend({

  id: null,
  name: null,
  description: null
});

MyCollection = Backbone.Collection.extend({ 
model: MyObject,
initialize: function (models,options) { }
});

Error:

Uncaught TypeError: Cannot use 'in' operator to search for 'id' in

Similar Issue: Backbone: fetch collection from server

My JSON certainly appears to be in the right format, am I missing something obvious? I have attempted using simply id: "1" as opposed to "id" with the same result.

回答1:

Your JSON is still in string format. Pass it to JSON.parse before assigning it:

var myJSON = JSON.parse('[{"id":1,"name":"some name","description":"hmmm"}]');

回答2:

You forgot the defaults hash in your model.

MyObject = Backbone.Model.extend({
  defaults: {
    id: null,
    name: null,
    description: null
  }
});

See the documentation

回答3:

so i maybe missing the point completely but the problems seems to be the 'single quotes' around the array. That is, this:

var myJSON = '[{ "id":"1","name":"some name","description":"hmmm"}]';

should be:

var myJSON = [{ "id":"1","name":"some name","description":"hmmm"}];

Php, afik, doesn't add the single quotes, so it should be as simple as changing a line that says:

$my_js = "var myJSON = '" . json_encode($my_array_to_send)) . "';";

to:

$my_js = "var myJSON = " . json_encode($my_array_to_send)) . ";  ";