BackboneJS collection.length
发布于 2015-08-14 15:21:58 | 109 次阅读 | 评论: 0 | 来源: 网络整理
计算集合中模型的数量一个属性。
语法
collection.length
示例
<!DOCTYPE html>
<head>
<title>Collection Example</title>
<script src="https://code.jquery.com/jquery-2.1.3.min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.2/underscore-min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.2/backbone-min.js" type="text/javascript"></script>
</head>
<body>
<script type="text/javascript">
//'Cities' is a model and contains defualt value for the model
var Cities = Backbone.Model.extend({
defaults: {
city: "Hyderabad"
}
});
//'CityCollection' is an instance of the collection
var CityCollection = Backbone.Collection.extend({
model: Cities //model 'Cities' is specified by using model property
});
//The add() method adds the models 'city1', 'city2' and 'city3' to the collection instance 'mycollection'
var city1 = new Cities({city: "Banglore"});
var city2 = new Cities({city: "Delhi"});
var city3 = new Cities({city: "Mumbai"});
var mycollection = new CityCollection();
mycollection.add([city1,city2,city3]);
document.write('Number of models in collection : ' + mycollection.length);
</script>
</body>
</html>
输出
让我们进行以下步骤来看看上面的代码工作：
-
保存上述代码到文件length.html
-
在浏览器打开这个HTML文件。
