使用js写cookie

	//写cookies  （关闭浏览器则失效）
		function setCookie(name, value) {
			var Days = 30;
			var exp = new Date();
			exp.setTime(exp.getTime() + Days * 24 * 60 * 60 * 1000);
			document.cookie = name + "=" + escape(value) ;
		}
		
		//读cookie
		function getCookie(name) {
			var arr, reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
			if(arr = document.cookie.match(reg))
				return unescape(arr[2]);
			else
				return null;
		}
		//删除cookie		
		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();
		}

		//写cookie的时间限制
		function setCookie(name, value, time) {
			var strsec = getsec(time);
			var exp = new Date();
			exp.setTime(exp.getTime() + strsec * 1);
			document.cookie = name + "=" + escape(value) + ";expires=" + exp.toGMTString();
		}

		function getsec(str) {
			alert(str);
			var str1 = str.substring(1, str.length) * 1;
			var str2 = str.substring(0, 1);
			if(str2 == "s") {
				return str1 * 1000;
			} else if(str2 == "h") {
				return str1 * 60 * 60 * 1000;
			} else if(str2 == "d") {
				return str1 * 24 * 60 * 60 * 1000;
			}
		}
		//使用示例：
		//s20是代表20秒
		//h是指小时，如12小时则是：h12
		//d是天数，30天则：d30