?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;
using System.Data.SqlClient;



public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void BtnLogin_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection("Server=.;Database=Mylibrary;UID=sa;Pwd=123;");
        string constring = "select * from  users where UserID='" + txtUserID.Text + "'and Pwd='" + txtPwd.Text + "'";
        con.Open();
        SqlCommand com = new SqlCommand(constring, con);
        SqlDataReader reader = com.ExecuteReader();
        if (reader.Read())
        {
            Session["UserID"] = reader[0];
            Response.Redirect("main.aspx");
        }
        else
        {
            Response.Write("<Script Language=JavaScript> alert(\"賬號或密碼不對，請核對后重新輸入！\")</Script>");
        }
    }
}