ASP.NET Cookie的使用汇总

１、解决Cookie更新滞后的问题
　　先写入一个过期的Cookie，再添加一个新的Cookie就ＯＫ了。示例代码如下所示：

protected void btnSearch_Click(object sender, EventArgs e)
        {
            //生成条件表达式
            string where = bll.GetWhereSql(Int32.Parse(ddlCate.SelectedValue),
                        Int32.Parse(ddlHarbor.SelectedValue), 0, 0, ddlState.SelectedValue, tbKeyword.Text.Trim());
            //判断条件Cookie是否为空，如不为空，则移除现有条件Cookie
            if (Request.Cookies["Admin_HarborSpot_Where"] != null)
            {
                RemoveWhereCookie(where);//移除现有条件Cookie
            }
            //设置一个新的条件Cookie
            SetWhereCookie(where);
            
            BindData(true);
        }

//设置条件Cookie
        private void SetWhereCookie(string where)
        {
            HttpCookie cookie = new HttpCookie("Admin_HarborSpot_Where");
            cookie.Value = where;
            cookie.Expires = DateTime.Now.AddDays(1d);
            Response.Cookies.Add(cookie);
        }

        //移除现存的条件Cookie
        private void RemoveWhereCookie(string where)
        {
            HttpCookie cookie = Request.Cookies["Admin_HarborSpot_Where"];
            cookie.Value = where;
            cookie.Expires = DateTime.Now.AddDays(-3d);
            Response.Cookies.Add(cookie);
        }