1、创建Cookies有两种方法:

Response.Cookies["userName"].Value = "patrick";
Response.Cookies["userName"].Expires = DateTime.Now.AddDays(1);
HttpCookie aCookie = new HttpCookie("lastVisit");
aCookie.Value = DateTime.Now.ToString();
aCookie.Expires = DateTime.Now.AddDays(1);
Response.Cookies.Add(aCookie);

2、读取Cookie

if(Request.Cookies["userName"] != null)
    Label1.Text = Server.HtmlEncode(Request.Cookies["userName"].Value);if(Request.Cookies["userName"] != null)
{
    HttpCookie aCookie = Request.Cookies["userName"];
    Label1.Text = Server.HtmlEncode(aCookie.Value);
}

3、修改和删除Cookie

int counter;if (Request.Cookies["counter"] == null)
    counter = 0;else{
    counter = int.Parse(Request.Cookies["counter"].Value);
}
counter++;

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

一定要注意设置Cookies是用Response读取是用Request两者不一样!

删除Cookie

string subkeyName;
subkeyName = "userName";
HttpCookie aCookie = Request.Cookies["userInfo"];
aCookie.Values.Remove(subkeyName);
aCookie.Expires = DateTime.Now.AddDays(1);
Response.Cookies.Add(aCookie);
HttpCookie aCookie;string cookieName;int limit = Request.Cookies.Count;for (int i=0; i<limit; i++)
{
    cookieName = Request.Cookies[i].Name;
    aCookie = new HttpCookie(cookieName);
    aCookie.Expires = DateTime.Now.AddDays(-1);
    Response.Cookies.Add(aCookie);
}