JS读、写、删cookie

function setCookie(name,value) {
	var Days = 30;//cookie保存30天
	var exp = new Date();
	exp.setTime(exp.getTime() + Days*24*60*60*1000);
	document.cookie = name + "=" + escape(value) + ";expires=" + exp.toGMTString();
}

function getCookie(name) {
	var arr,reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
	if (arr = document.cookie.match(reg)) {
		return unescape(arr[2]);
	} else {
		return null;
	}
}

function delCookie(name) {
	var exp = new Date();
	exp.setTime(exp.getTime() - 1);
	var cval=getCookie(name);
	if(cval!=null)
	document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}