BackboneJS 模型非空验证
2018-01-05 11:24 更新
描述
如果属性设置为非空值或非未定义值,则此方法返回true。
语法model.has(attribute)
model.has(attribute)
参数
attribute:属性定义创建的模型的属性。
例<!DOCTYPE html>
<head>
<title> Model 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>
<script type="text/javascript">
var Company = Backbone.Model.extend();
var company=new Company();
company.set({ Name: "TutorialsPoint", comp_site:"www.tutorialspoint.com"});
if(company.has('comp_site'))
{
document.write("The model Company has site: True");
}
else
{
document.write("The model Company has site: False");
}
</script>
</head>
<body></body>
</html>
<!DOCTYPE html>
<head>
<title> Model 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>
<script type="text/javascript">
var Company = Backbone.Model.extend();
var company=new Company();
company.set({ Name: "TutorialsPoint", comp_site:"www.tutorialspoint.com"});
if(company.has('comp_site'))
{
document.write("The model Company has site: True");
}
else
{
document.write("The model Company has site: False");
}
</script>
</head>
<body></body>
</html>
输出
让我们执行以下步骤,看看上面的代码如何工作:- 将上面的代码保存在has.htm文件中。
- 在浏览器中打开此HTML文件。
The model Company has site: True
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