js 取cookie 设置cookie删cookie

	//取cookies函数
		function getCookie(name){
		 	var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));
		 	if (arr != null) return unescape(arr[2]); return null;
		}
		//两个参数，一个是cookie的名子，一个是值
		function setCookie(name,value){
		 	var Days = 1;//此 cookie 将被保存 1 天
		 	var exp = new Date();//new Date("December 31, 9998");
		 	exp.setTime(exp.getTime() + 30*60*1000);
		 	document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
		}

		// 删除cookies
		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();
		}