Knockoutjs.com - Hello World Example

http://knockoutjs.com/examples/helloWorld.html

by gavinfoley

HTML

<script src="http://cloud.github.com/downloads/SteveSanderson/knockout/knockout-2.2.0.js"></script>
<div class='liveExample'>   
    <p>First name: <input data-bind="value: firstName, valueUpdate:'afterkeydown'" /></p> 
    <p>Last name: <input data-bind="value: lastName, valueUpdate:'afterkeydown'" /></p> 
    <h2><span data-bind='text: fullName'></span></h2>  
</div>

CSS

body { font-family: arial; font-size: 14px; }
.liveExample { padding: 1em; background-color: #EEEEDD; border: 1px solid #CCC; max-width: 655px; }
.liveExample input { font-family: Arial; }
.liveExample b { font-weight: bold; }
.liveExample p { margin-top: 0.9em; margin-bottom: 0.9em; }
.liveExample select[multiple] { width: 100%; height: 8em; }
.liveExample h2 { margin-top: 0.4em; font-weight: bold; font-size: 1.2em; }

JavaScript

// Here's my data model
var ViewModel = function(first, last) {
    this.firstName = ko.observable(first);
    this.lastName = ko.observable(last);

    this.fullName = ko.computed(function() {
        // Knockout tracks dependencies automatically. It knows that fullName depends on firstName and lastName, because these get called when evaluating fullName.
        var name = $.trim(this.firstName() + " " + this.lastName());
        if (name.length > 1) return "Hello, " + name + "!";
        return "";
    }, this);
};

ko.applyBindings(new ViewModel("", "")); // This makes Knockout get to work