function addCookie(objName,objValue,objHours)
		{//添加cookie
			var str = objName + "=" + escape(objValue);
			//为0时不设定过期时间，浏览器关闭时cookie自动消失
			if(objHours > 0)
			{
				var date = new Date();
				var ms = objHours*3600*1000;
				date.setTime(date.getTime() + ms);
				str += "; expires=" + date.toGMTString();
			}
			document.cookie = str;
			alert("添加cookie成功");
		}
		//获取指定名称的cookie的值
		function getCookie(objName)
		{
			var arrStr = document.cookie.split("; ");
			for(var i = 0;i < arrStr.length;i ++)
			{
				var temp = arrStr[i].split("=");
				if(temp[0] == objName) return unescape(temp[1]);
			} 
		}
		//为了删除指定名称的cookie，可以将其过期时间设定为一个过去的时间
		function delCookie(name)
		{
			var date = new Date();
			date.setTime(date.getTime() - 10000);
			document.cookie = name + "=a; expires=" + date.toGMTString();
		}
		//读取所有保存的cookie字符串
		function allCookie()
		{
			var str = document.cookie;
			if(str == "")
			{
				str = "没有保存任何cookie";
			}
			alert(str);
		}
		
		function $(m,n)
		{
			return document.forms[m].elements[n].value;
		}
		
		function add_()
		{
			var cookie_name = $("myform","cookie_name");
			var cookie_value = $("myform","cookie_value");
			var cookie_expireHours = $("myform","cookie_expiresHours");
			addCookie(cookie_name,cookie_value,cookie_expireHours);
		}
		
		function get_(){
			var cookie_name = $("myform","cookie_name");
			var cookie_value = getCookie(cookie_name);
			alert(cookie_value);
		}
		
		function del_(){
			var cookie_name = $("myform","cookie_name");
			delCookie(cookie_name);
			alert("删除成功");
		}