Programatically add new roles

Hello
I want to add a new role by code

I try to use (roles.RoleExists) and (roles.CreateRole)
But
I fount that those methods are not implemented

I am really I need to implement these methods, 

can any one lead me , I am lost because of removing the membership framework :(
this is my code
Imports System.Web.Security Public Class roles Inherits System.Web.UI.Page Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load End Sub Protected Sub showAddRoleBlock_Click(sender As Object, e As EventArgs) Handles showAddRoleBlock.Click addRoleBlock.Visible = True End Sub Protected Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click newRoleTextBox.Text = "" addRoleBlock.Visible = False End Sub Protected Sub Button2_Cl ...