knockout.js observable没有更新

Viv*_*Dev 0 html javascript jquery observable knockout.js

球队,

我有一个非常简单的html页面,其中包含一个viewmodel,如下所示.

@{
    Layout = null;
}
<!DOCTYPE html>
<html>
<head>
    <script src='E:\Trials\ClientSide\MyTrials\knockout-2.2.1.js' type='text/javascript'></script>
    <script src='E:\Trials\ClientSide\MyTrials\jquery-2.0.0.js' type='text/javascript'></script>
    <title>Index</title>
    <script type="text/javascript">

        function PersonViewModel()
        {
            firstName = ko.observable("FirstN")
        };

        $(document).ready(function () {
            var person = new PersonViewModel();
            ko.applyBindings(person);
        });

    </script>
</head>
<body>
    <div>
        <h3>Details</h3>
        <p>First Name: <input data-bind="value:  firstName()" /></p>
        <p>First Name From span: <span data-bind="text: firstName()" ></span> </p>
    </div>
</body>
</html>
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它非常简单和自我解释.脚本块包含一个视图模型,在doc ready函数上,绑定发生.而且html也很简单.一个输入和一个跨度绑定到可观察的相同属性firstName.但痛苦是当我从输入中更改值时,跨度不会更新.我错过了什么?关心Vivek

Cla*_*edi 7

更改firstName()firstName

<p>First Name: <input data-bind="value:  firstName" /></p>
<p>First Name From span: <span data-bind="text: firstName" ></span> </p>
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