?using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            if (Session["username"] == null)
                Response.Redirect("login.aspx");
            else

              Label1.Text=(Session["username"] + "歡迎進入系統");


        }
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        Session.Remove("username");        
        Response.Redirect("login.aspx");
    }
}