C# - Implement Custom MembershipUser And MembershipProvider

I try to implement a Custom MembershipPriver with a Custom MemberShipUser in my own database (with a specifics Users Table Model) : This is ly diffent files:

iTwitterMembershipProvider.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Collections.Specialized;
using iTwitter.Models;
public class iTwitterMembershipProvider : MembershipProvider
{
public override string ApplicationName
{
get { return _ApplicationName; }
set { _ApplicationName = value; }
}
public override bool ChangePassword(string username, string oldPassword, string newPassword)
{
throw new NotImplementedException();
}
public override bool ChangePasswordQuestionAndAnswer(string username, string password, string newPasswordQuestion, string newPasswordAnswer)
{
return false;
}
public override iTwitterMembershipUser CreateUser(string login,
string password,
string email,
string tokenKey,
string tokenSecret,
string twitterUserId,
object providerUserKey,
out MembershipCreateStatus status)
{
ValidatePasswordEventArgs args = new ValidatePasswordEventArgs(login,
password,
true);

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