TBra 是淘宝的JavaScript开发框架，基于YUI，目前包含的组件包括:

• TB.common
• TB.dom
• TB.bom
• TB.util
• TB.widget
• TB.form

Next

			(function() {
				var ua = navigator.userAgent.toLowerCase();
				var _isOpera = ua.indexOf('opera') != -1,
					_isSafari = ua.indexOf('safari') != -1,
					_isGecko = !_isOpera && !_isSafari && ua.indexOf('gecko') > -1,
					_isIE = !_isOpera && ua.indexOf('msie') != -1, 
					_isIE6 = !_isOpera && ua.indexOf('msie 6') != -1;
					
				TB.bom = {
					isOpera: _isOpera,
					isSafari: _isSafari,
					isGecko: _isGecko,
					isIE: _isIE,
					isIE6: _isIE6
				}
			});