Response.Cookies["UserName"].Value="Guest";
Response.Cookies["UserName"].Expires=DateTime.Now.AddDays(1);

 HttpCookie userName_zhengshu_Cookie = new HttpCookie("uname");
        userName_zhengshu_Cookie.Value = "陈xx";

        HttpCookie userLession_zhengshur_Cookie = new HttpCookie("lcode");
        userLession_zhengshur_Cookie.Value = "chen jian ping";

        userName_zhengshu_Cookie.Path = "/";
        userLession_zhengshur_Cookie.Path = "/";

//限定有效期
        userLession_zhengshur_Cookie.Expires = DateTime.Now.AddDays(1);
        userName_zhengshu_Cookie.Expires = DateTime.Now.AddDays(1);

        Response.Cookies.Add(userLession_zhengshur_Cookie);
        Response.Cookies.Add(userName_zhengshu_Cookie);

//Cookies添加
 Response.AppendCookie(user_cookies);

//取值
Response.Write(Request.Cookies["uname"].Value);

//javascript写读Cookie
function Set_Cookie()
{
    var setValue="陈xx";
    var exdate=new Date();
    exdate.setDate(exdate.getDate()+365);
    document.cookie="userLession"+ "=" +setValue+";expires="+exdate.toGMTString()+";path=/";
    alert("已经写入Cookie");
}

 function Get(){　     
   　　var cookieString=new String(document.cookie)     
   　　var cookieHeader = "userLession="     
   　　var beginPosition = cookieString.indexOf(cookieHeader)     
   　　if(beginPosition != -1)
   　　{     
   　　　　alert(cookieString.substring(cookieHeader.length,cookieString.indexOf(";")));  
   　　}     
   }