How to hide login button when user logged in show logout button in asp.net vb?

Question

Protected Sub btnloginp1_Click(sender As Object, e As EventArgs) Handles btnloginp1.Click
        If logemail.Text = "" Or logpassw.Text = "" Then
            lbl_msg_log.Text = "Enter Email address and Password"
        Else
            lbl_msg_signup.Text = ""
            Dim conn As New SqlConnection
            Dim constr As String
            constr = "Data Source=LAPTOP-CAK7UT2M;Initial Catalog=MyProjectUService;Integrated Security=True"
            conn.ConnectionString = constr
            conn.Open()
            Dim sql = "select * from Login where login_email='" & logemail.Text & "' and login_password='" & logpassw.Text & "'"
            Dim comm As New SqlCommand(sql, conn)
            Dim dr As SqlDataReader
            dr = comm.ExecuteReader
            Dim a
            If dr.Read() = True Then
                a = 1
            Else
                a = 0
            End If
            dr.Close()
            conn.Close()
             
            btn_login.visible=false
            
            Dim btnn As New Button
            //above is login button which i want to hide when user successful logged and show below signout button   
            btnn.Text = "SignOut"
            plhadd.Controls.Add(btnn)
        End If
    End Sub