校验浏览器

<SCRIPT LANGUAGE="JavaScript">
<!--
var JsBase={};
JsBase.apply = function(o, c){
    if(o && c && typeof c == 'object'){
        for(var p in c){
            o[p] = c[p];
        }
    }
    return o;
};
(function(){
    var ua = navigator.userAgent.toLowerCase();

    var isOpera = ua.indexOf("opera") > -1,
        isIE = ua.indexOf("msie") > -1,
        isIE7 = ua.indexOf("msie 7") > -1,
        isGecko = ua.indexOf("gecko") > -1;
	JsBase.apply(JsBase,{
	    isOpera : isOpera,
		isIE : isIE,
		isIE7 : isIE7,
		isGecko : isGecko,
		descObject : function(o){
			var ret='';
			if(typeof o == 'object'){
				for(key in o){
					ret+=key+':'+o[key]+'\r\n';

				}
			}
			return ret;
		}
	});
})();
alert(JsBase.descObject(JsBase))
//-->
</SCRIPT>