event handler

基本解釋

It provides an event handler for each menu option.
它為每一個(gè)菜單選項(xiàng)提供事件處理程序。
If the global scope requires the result of the event handler, set the result in the global result variable.
如果全局范圍要求使用事件處理程序的結(jié)果，請(qǐng)?jiān)谌纸Y(jié)果變量中設(shè)置該結(jié)果。
To see why, imagine you have a button in your application. You want to do some work when the button is clicked, so you add an event handler to it.
為了了解原因，您可以設(shè)想應(yīng)用程序上有一個(gè)按鈕，單擊按鈕時(shí)要做一些工作，于是您對(duì)它添加了一個(gè)事件處理程序。