写入、读取、清除Cookie的类

/// <summary>
  /// 保存一个Cookie
  /// </summary>
  /// <param name="CookieName">Cookie名称</param>
  /// <param name="CookieValue">Cookie值</param>
  /// <param name="CookieTime">Cookie过期时间(小时),0为关闭页面失效</param>
  public void SaveCookie(string CookieName,string CookieValue,double CookieTime)
  {
   HttpCookie myCookie = new HttpCookie(CookieName);
   DateTime now = DateTime.Now; 
   myCookie.Value = CookieValue;

   if(CookieTime!=0)
   {
    myCookie.Expires = now.AddDays(CookieTime);
    if(HttpContext.Current.Response.Cookies[CookieName]!=null)
     HttpContext.Current.Response.Cookies.Remove(CookieName);

    HttpContext.Current.Response.Cookies.Add(myCookie);
   }
   else
   {
    if(HttpContext.Current.Response.Cookies[CookieName]!=null)
     HttpContext.Current.Response.Cookies.Remove(CookieName);

    HttpContext.Current.Response.Cookies.Add(myCookie);
   }
  }


  /// <summary>
  /// 取得CookieValue
  /// </summary>
  /// <param name="CookieName">Cookie名称</param>
  /// <returns>Cookie的值</returns>
  public string GetCookie(string CookieName)
  {
   HttpCookie myCookie = new HttpCookie(CookieName);
   myCookie = HttpContext.Current.Request.Cookies[CookieName];

   if (myCookie != null)
    return myCookie.Value;
   else
    return null;
  }


 /// <summary>
  /// 清除CookieValue
  /// </summary>
  /// <param name="CookieName">Cookie名称</param>
  public void ClearCookie(string CookieName)
  {
   HttpCookie myCookie = new HttpCookie(CookieName);
   DateTime now = DateTime.Now;

   myCookie.Expires = now.AddYears(-2);

   HttpContext.Current.Response.Cookies.Add(myCookie);
  }