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BackboneJS 模型非空驗證
2018-01-05 11:24 更新
描述
如果屬性設(shè)置為非空值或非未定義值，則此方法返回true。
語法model.has(attribute)
model.has(attribute)
參數(shù)
attribute：屬性定義創(chuàng)建的模型的屬性。
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>
輸出
讓我們執(zhí)行以下步驟，看看上面的代碼如何工作：- 將上面的代碼保存在has.htm文件中。
- 在瀏覽器中打開此HTML文件。
The model Company has site: True以上內(nèi)容是否對您有幫助：
更多建議：