name: Function.bindAsEventListener
This provides a new method to the core class Function. The method,called bindAsEventListener(),is used to do bind methods to event handlers.
這為核心class 函數支持了一個新的方法。這個方法叫bindAsEventListener(),是用來綁定方法給事件處理器的。
var obj = new SomeClass();
var closure = obj.someMethod.bindAsEventListener(this);
element.onclick = closure;