我已经定义了我的模型和它的默认变量;然而，每当我试图在模型本身内部使用这些变量中的任何一个时，它们的值都被设置为“未定义”。

JAWeatherWatch.module('Cities', function(Cities, JAWeatherWatch, Backbone, Marionette){

        /*  Cities
        *   This model is used to model the datat retued by the open weather api 
        *   for each individual city in jamaica
        */
        Cities.City = Backbone.Model.extend({
            defaults:{
                // stores my api key as well the required query string to add to the request
                apiKey: '&APPID=84cb7efaf4ac2947aa6381637904ee5e',
                country:'jamaica',
                parishName: false
            }, 
            url:'http://api.openweathermap.org/data/2.5/weather?q=' + this.parishName  + "," + this.country + this.apiKey,
            initialize: function(){

                console.log(this.country); // => 'undefined'

                // todo: get json data from api
            }
        });

    });

    var test = new JAWeatherWatch.Cities.City({parishName:'kingston'});
    console.log(test.get('country')) // => 'jamaica'

奇怪的是，在模型示例化之后，它们的行为和预期的一样（即返回正确的值）。