ExtJS 2.0 Practical and Concise Tutorial: Introduction to Ext Class Library_extjs

The ExtJS class library is composed of the following parts:
The underlying API (core): The underlying API provides basic functions such as DOM operations, query encapsulation, event processing, and DOM queryers. Other controls are built on the basis of these underlying APIs. The underlying APIs are located in the core subdirectory of the source code directory, including DomHelper.js, Element.js and other files, as shown in Figure xx.

Controls (widgets): Controls refer to visual components that can be created directly on the page, such as panels, palettes, tables, trees, windows, menus, toolbars, Buttons, etc., we can directly apply these controls in our applications to achieve a friendly and interactive application UI. The control is located in the widgets subdirectory of the source code directory, as shown in Figure xx.

Utils: Ext provides a lot of practical tools, which can facilitate us to implement functions such as data content formatting, JSON data decoding or decoding, Date, Array, sending Ajax requests, cookie management, CSS management and other extensions. , as shown in the picture: