目前Knockout.js的教程和视频也有不少，但好多都是1.x版本的，而官方的更新也是很积极。
所以我直接选择通过官方的小教程来学习。正好也可以亲身体验一下MVVM。
①将数据绑定到DOM
<!DOCTYPE HTML> <html> <head> <script src="http://knockoutjs.com/js/jquery-1.4.2.min.js"></script> <script src="http://cdnjs.cloudflare.com/ajax/libs/knockout/2.1.0/knockout-min.js"></script> </head> <body> <!-- This is a *view* - HTML markup that defines the appearance of your UI --> <hr /> <h3>绑定前：</h3> <p>First name: <strong>todo</strong></p> <p>Last name: <strong>todo</strong></p> <hr /> <h3>绑定后：</h3> <p>First name: <strong data-bind="text:firstName">todo</strong></p> <p>Last name: <strong data-bind="text:lastName">todo</strong></p> <script type="text/javascript"> // This is a simple *viewmodel* - JavaScript that defines the data and behavior of your UI function AppViewModel() { this.firstName = "Bert"; this.lastName = "Bertington"; } // Activates knockout.js ko.applyBindings(new AppViewModel()); </script> </body> </html>
效果：
②监听DOM的变化
当input内容变化时，绑定到该DOM的数据也会变化，随之而来的就是绑定了该数据的DOM也会更新。
<!DOCTYPE HTML> <html> <head> <script src="http://knockoutjs.com/js/jquery-1.4.2.min.js"></script> <script src="http://cdnjs.cloudflare.com/ajax/libs/knockout/2.1.0/knockout-min.js"></script> </head> <body> <!-- This is a *view* - HTML markup that defines the appearance of your UI --> <p>First name: <strong data-bind="text: firstName"></strong></p> <p>Last name: <strong data-bind="text: lastName"></strong></p> <p>First name: <input data-bind="value: firstName" /></p> <p>Last name: <input data-bind="value: lastName" /></p> <script type="text/javascript"> // This is a simple *viewmodel* - JavaScript that defines the data and behavior of your UI function AppViewModel() { this.firstName = ko.observable("Bert"); //ko.observable是监听firstName的关键。里面的参数是其初始值 this.lastName = ko.observable("Bertington"); } var model = new AppViewModel(); // Activates knockout.js ko.applyBindings(model); </script> </body> </html>
③某个DOM的值依赖于 绑定的数据计算后的结果；连接View和ViewModel的事件。
<!DOCTYPE HTML> <html> <head> <script src="http://knockoutjs.com/js/jquery-1.4.2.min.js"></script> <script src="http://cdnjs.cloudflare.com/ajax/libs/knockout/2.1.0/knockout-min.js"></script> </head> <body> <p>First name: <strong data-bind="text: firstName"></strong></p> <p>Last name: <strong data-bind="text: lastName"></strong></p> <p>First name: <input data-bind="value: firstName" /></p> <p>Last name: <input data-bind="value: lastName" /></p> <p>Full name: <strong data-bind="text: fullName" ></strong></p> <input type="button" data-bind="click:toUpper" value="To Upper" /> <script type="text/javascript"> // This is a simple *viewmodel* - JavaScript that defines the data and behavior of your UI function AppViewModel() { this.firstName = ko.observable(""); this.lastName = ko.observable(""); this.fullName = ko.computed(function() { return this.firstName() + "--" + this.lastName(); }, this); this.toUpper = function() { var c = this.lastName(); this.lastName(c.toUpperCase()); }; } var model = new AppViewModel(); // Activates knockout.js ko.applyBindings(model); </script> </body> </html>