4.1. Introducing Atlas Client Controls

Atlas implements its client controls in the Sys.UI namespace. Sys.UI is the client-side equivalent of the similarly named and well-known Web.UI namespace in ASP.NET.

In older Atlas releases, the client-side namespace was named Web.UI, as well.

Sys.UI contains a large number of Atlas HTML controls and web controls. The functionality of Atlas controls is similar but not identical to ASP.NET server controls. Atlas controls provide a consistent, browser-independent model that enables JavaScript code to access and change client controls properties, something that with non-Atlas controls would require quite a bit of JavaScript knowledge as well as some workarounds for browser inconsistencies.

Table 4-1 lists controls provided by Atlas. The table lists the HTML elements that the Atlas control works with and the equivalent DOM object or method that you would use in JavaScript.

Table 4-1. Atlas controls

Atlas control	Description	HTML element	JavaScript equivalent
Sys.UI.Window	Implements JavaScript pop-up windows	N/A	window.alert(), window.confirm(), window.prompt()
Sys.UI.Label	Implements a span or label element	<span>, <label>	label
Sys.UI.Image	Implements an image	<img>	image
Sys.UI.HyperLink	Implements a link	<a href="...">	link
Sys.UI.Button	Implements a button	<input type="button">, <input type="submit">, <input type="reset">, <button>	button, submit, reset
Sys.UI.CheckBox	Implements a checkbox	<input type="checkbox">	checkbox
Sys.UI.Select	Implements a selection list	<select>	select
Sys.UI.TextBox	Implements a text field	<input type="text">, <input type="password">, <textarea>	text, password, textarea