LogIn Mechanism Using 3-tier

Use this code where you want to display like Welcome,"UserName":

<asp:LoginView runat="server" ID="LoginView1">
                                            <AnonymousTemplate>
                                                Welcome Guest,
                                                <asp:LoginStatus runat="server" ID="LoginStatus1" />
                                            </AnonymousTemplate>
                                            <LoggedInTemplate>
                                                Welcome
                                                <asp:LoginName runat="server" ID="LoginName1" />
                                                ,
                                                <asp:LoginStatus runat="server" ID="LoginStatus1" />
                                            </LoggedInTemplate>
                                        </asp:LoginView>

And, LogIn using 3-tier:
UI Layer:
LogIn.aspx:

<asp:Login ID="Login1" runat="server" BackColor="#EFF3FB" BorderColor="#B5C7DE" BorderPadding="4"
            BorderStyle="Solid" BorderWidth="1px" Font-Names="Verdana" Font-Size="1em"
            ForeColor="#333333" OnAuthenticate="Login1_Authenticate">
            <InstructionTextStyle Font-Italic="True" ForeColor="Black" />
            <LoginButtonStyle BackColor="White" BorderColor="#507CD1" BorderStyle="Solid" BorderWidth="1px"
                Font-Names="Verdana" Font-Size="0.8em" ForeColor="#284E98" />
            <TextBoxStyle Font-Size="0.8em" />
            <TitleTextStyle BackColor="#507CD1" Font-Bold="True" Font-Size="0.9em" ForeColor="White" />
        </asp:Login>

Code Behind:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.Security;
using System.Data.SqlClient;
using System.Configuration;
using DotNetFundaBAL;

public partial class LogIn : System.Web.UI.Page
{
    string connStr = ConfigurationManager.ConnectionStrings["ConnStr"].ToString();
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Login1_Authenticate(object sender, AuthenticateEventArgs e)
    {
        bool isAuthenticated = false;
        ArticleBAL b = new ArticleBAL();
        string UserName = Login1.UserName;
        string Password = Login1.Password;
        object obj = b.LogIn(UserName, Password);
        if (obj != null)
        {
            isAuthenticated = true;
        }
       

        if (isAuthenticated)
        {
            FormsAuthentication.RedirectFromLoginPage(Login1.UserName, Login1.RememberMeSet);


        }
    }
}

In DAL Class write This Method:

 public object LogIn(string UserName, string Password)
        {
            using (SqlConnection conn = new SqlConnection(_constr))
            {
                string sql = "SELECT CustomerId from Registration WHERE UserName = @UserName AND Password = @Password";
                using (SqlCommand cmd = new SqlCommand(sql, conn))
                {
                    cmd.Parameters.AddWithValue("@UserName", UserName);
                    cmd.Parameters.AddWithValue("@Password", Password);
                    conn.Open();
                    object obj = cmd.ExecuteScalar();
                    conn.Close();
                    return obj;
                    
                    
                }
            }
        }

In BAL add this method:

public object LogIn(string UserName, string Password)
        {
            ArticleDAL i = new ArticleDAL();
            return i.LogIn(UserName, Password);
        }

web.config:

<authentication mode="Forms">
            <forms defaultUrl="~/Forums.aspx" loginUrl="~/LogIn.aspx" slidingExpiration="true" timeout="20"/>
        </authentication>

Thanks & regards