using System;
using System.Web;

namespace WebApplication4
{
    /// <summary>
    /// ASP.NET Session 操作, 以用戶登錄退出為例, 實現Session的獲取, 設置, 清除
    /// </summary>
    public partial class Default : System.Web.UI.Page
    {
        /// <summary>
        /// 載入, 獲取Session
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void Page_Load(object sender, EventArgs e)
        {
            string user = "";
            // 讀取Session
            if (HttpContext.Current.Session["User"] != null)
            {
                user= HttpContext.Current.Session["User"].ToString();
            }
            Response.Write("當前登錄用戶: " + user);
        }

        /// <summary>
        /// 登錄, 設置Session
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void btnLogin_Click(object sender, EventArgs e)
        {
            // 設置Session, 5分鐘后過期
            HttpContext.Current.Session["User"] = "Admin";
            HttpContext.Current.Session.Timeout = 5;

            // 再次刷新頁面
            HttpContext.Current.Response.Redirect("Default.aspx", false);
        }

        /// <summary>
        /// 退出, 清除Session
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void btnLogOff_Click(object sender, EventArgs e)
        {
            // 清除Session
            if (HttpContext.Current.Session != null)
            {
                HttpContext.Current.Session["User"] = null;
            }

            // 再次刷新頁面
            HttpContext.Current.Response.Redirect("Default.aspx", false);
        }
    }
}