backbone.js快速入门（四）

编写第一个backbone应用：

1，通过backbone.model对象来定义我们的模型

var InvoiceItemModel =new Backbone.Model.extend({

defaults:{

price:0,

puantity:0

},

calculateAmount: function（）{

return this.get（‘price’）* this.geyanti');

}

}); 

2，创建一个模型实例

var InvoiceItemModel = new InvoiceItemModel({

price:2,

quantity:3

});

3，定义一个负责对模型进行渲染的视图

var PreviewInvoiceItemView = Backbone.View,extend({

//underscore.js

template:_.template('\

price:<%=price%>.\

quantity:<% = quantity %>.\

amount:<% amount %>.\

'),

render:function(){

var html= this.template({

price:this.model.get('price'),

quantity:this.model.get('quantity'),

amount:this.model.calculateAmount()

});

$(this.el).html(html);

}

})；

创建时传入的属性this.model和this.el

var previewInvoiceItemView = new PreviewInvoiceItemView({

model:invoiceItemModel,

el: 'body'

});

4，要渲染一个视图，只需执行视图对象的render（）方法

previewInvoiceItemView.render();

5，运行应用

$(document).ready(function(){

var invoiceItemModel = new InvoiceItemModel ({

price:2,

quantity:3

});

var previewInvoiceItemView = new previewInvoiceItemView ({

model:invoiceItemModel,

el:'body'

});

});