function getCookieVal(offset) {
	//获得Cookie解码后的值
	var endstr = document.cookie.indexOf(";", offset);
	if (endstr == -1) {
		endstr = document.cookie.length;
	}
	return unescape(document.cookie.substring(offset, endstr));
}
function GetCookie(name) {
	//获得Cookie的原始值
	var arg = name+"=";
	var alen = arg.length;
	var clen = document.cookie.length;
	var i = 0;
	while (i<clen) {
		var j = i+alen;
		if (document.cookie.substring(i, j) == arg) {
			return getCookieVal(j);
		}
		i = document.cookie.indexOf(" ", i)+1;
		if (i == 0) {
			break;
		}
	}
	return null;
}

function SetCookie(name, value, expires, path) {
	//设定Cookie值
	var exp = new Date(); 
	exp.setTime(exp.getTime() + (expires*24*60*60*1000));
	var argv = SetCookie.arguments;
	var argc = SetCookie.arguments.length;
	var expires = (2<argc) ? argv[2] : null;
	var path = (3<argc) ? argv[3] : null;
	var domain = (4<argc) ? argv[4] : null;
	var secure = (5<argc) ? argv[5] : false;
	document.cookie = name+"="+escape(value)+((expires == null || expires==0) ? "" : ("; expires="+exp.toGMTString()))+((path == null) ? "" : ("; path="+path))+((domain == null) ? "" : ("; domain="+domain))+((secure == true) ? "; secure" : "");
}   
function DeleteCookie(name) {
	var exp = new Date();
	exp.setTime(exp.getTime()-1);
	var cval = GetCookie(name);
	document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString() + "; path=/;"; 

}
function Clearcookie() {
	var temp = document.cookie.split(";");
	var loop3;
	var ts;
	for (loop3=0; loop3<temp.length; loop3++) {
		ts = temp[loop3].split("=")[0];
		if (ts.indexOf('mycat') != -1) {
			DeleteCookie(ts);
		}
		//如果ts含“mycat”则执行清除 
	}
}