' ***********************************************************************
' Author   : Elektro
' Modified : 20-June-2015
' ***********************************************************************
' <copyright file="UserAccountUtil.vb" company="Elektro Studios">
'     Copyright (c) Elektro Studios. All rights reserved.
' </copyright>
' ***********************************************************************
 
#Region " Public Members Summary "
 
#Region " Properties "
 
' UserAccountUtil.CurrentUser As UserPrincipal
' UserAccountUtil.CurrentUserIsAdmin As Boolean
 
#End Region
 
#Region " Functions "
 
' UserAccountUtil.Create(String, String, String, String, Boolean, Boolean) As UserPrincipal
' UserAccountUtil.FindProfilePath(SecurityIdentifier) As String
' UserAccountUtil.FindProfilePath(String) As String
' UserAccountUtil.FindSid(String) As SecurityIdentifier
' UserAccountUtil.FindUser(SecurityIdentifier) As UserPrincipal
' UserAccountUtil.FindUser(String) As UserPrincipal
' UserAccountUtil.FindUsername(SecurityIdentifier) As String
' UserAccountUtil.GetAllUsers() As List(Of UserPrincipal)
' UserAccountUtil.IsAdmin(String) As Boolean
' UserAccountUtil.IsMemberOfGroup(String, String) As Boolean
' UserAccountUtil.IsMemberOfGroup(String, WellKnownSidType) As Boolean
 
#End Region
 
#Region " Methods "
 
' UserAccountUtil.Add(String, String, String, String, Boolean, Boolean, WellKnownSidType)
' UserAccountUtil.Add(UserPrincipal, WellKnownSidType)
' UserAccountUtil.Delete(String)
 
#End Region
 
#End Region
 
#Region " Option Statements "
 
Option Strict On
Option Explicit On
Option Infer Off
 
#End Region
 
#Region " Imports "
 
Imports System
Imports System.Collections.Generic
Imports System.DirectoryServices.AccountManagement
Imports System.Linq
Imports System.Security.Principal
 
#End Region
 
''' <summary>
''' Contains related Windows user-account utilities.
''' </summary>
Public NotInheritable Class UserAccountUtil
 
#Region " Properties "
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Gets an <see cref="UserPrincipal"/> object that represents the current user.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <value>
    ''' An <see cref="UserPrincipal"/> object that represents the current user.
    ''' </value>
    ''' ----------------------------------------------------------------------------------------------------
    Public Shared ReadOnly Property CurrentUser As UserPrincipal
        Get
            If UserAccountUtil.currentUserB Is Nothing Then
                UserAccountUtil.currentUserB = UserAccountUtil.FindUser(Environment.UserName)
            End If
            Return UserAccountUtil.currentUserB
        End Get
    End Property
    ''' <summary>
    ''' (Backing Field)
    ''' Gets an <see cref="UserPrincipal"/> object that represents the current user.
    ''' </summary>
    Private Shared currentUserB As UserPrincipal
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Gets a value that indicates whether the current user has Administrator privileges.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <value>
    ''' A value that indicates whether the current user has Administrator privileges.
    ''' </value>
    ''' ----------------------------------------------------------------------------------------------------
    Public Shared ReadOnly Property CurrentUserIsAdmin As Boolean
        Get
            Using group As GroupPrincipal =
                GroupPrincipal.FindByIdentity(CurrentUser.Context,
                                              IdentityType.Sid,
                                              New SecurityIdentifier(WellKnownSidType.BuiltinAdministratorsSid, Nothing).Value)
 
                Return UserAccountUtil.CurrentUser.IsMemberOf(group)
            End Using
        End Get
    End Property
 
#End Region
 
#Region " Constructors "
 
    ''' <summary>
    ''' Prevents a default instance of the <see cref="UserAccountUtil"/> class from being created.
    ''' </summary>
    Private Sub New()
    End Sub
 
#End Region
 
#Region " Public Methods "
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Get all user-accounts.
    ''' Author: Elektro
    ''' Date  : 20-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim users As List(Of UserPrincipal) = UserAccountUtil.GetAllUsers()
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Find and returns all the user accounts of the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' A <see cref="List(Of UserPrincipal)"/> collection that contains the users.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function GetAllUsers() As List(Of UserPrincipal)
 
        Dim context As New PrincipalContext(ContextType.Machine)
 
        Using user As New UserPrincipal(context)
 
            Using searcher As New PrincipalSearcher(user)
 
                Return searcher.FindAll.Cast(Of UserPrincipal).ToList
 
            End Using ' searcher
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account by name.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim user As UserPrincipal = UserAccountUtil.FindUser(username:="Administrator")
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds an user account that matches the specified name in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name to find.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' An <see cref="UserPrincipal"/> object that contains the user data.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <exception cref="ArgumentException">
    ''' User not found.;username
    ''' </exception>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindUser(ByVal username As String) As UserPrincipal
 
        Dim context As New PrincipalContext(ContextType.Machine)
 
        Using user As New UserPrincipal(context)
 
            Using searcher As New PrincipalSearcher(user)
 
                Try
                    Return (From p As Principal In searcher.FindAll
                            Where p.Name.Equals(username, StringComparison.OrdinalIgnoreCase)).
                            Cast(Of UserPrincipal).
                            First
 
                Catch ex As InvalidOperationException
                    Throw New ArgumentException(message:="User not found.", paramName:="username", innerException:=ex)
 
                End Try
 
            End Using ' searcher
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account by SID.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim user As UserPrincipal = UserAccountUtil.FindUser(sid:=New SecurityIdentifier("S-1-5-21-1780771175-1208154119-2269826705-500"))
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds an user account that matches the specified security identifier (SID) in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="sid">
    ''' A <see cref="SecurityIdentifier"/> (SID) object.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' An <see cref="UserPrincipal"/> object that contains the user data.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindUser(ByVal sid As SecurityIdentifier) As UserPrincipal
 
        Dim context As New PrincipalContext(ContextType.Machine)
 
        Using user As New UserPrincipal(context)
 
            Using searcher As New PrincipalSearcher(user)
 
                Try
                    Return (From p As Principal In searcher.FindAll
                            Where p.Sid.Value.Equals(sid.Value, StringComparison.OrdinalIgnoreCase)).
                            Cast(Of UserPrincipal).
                            First
 
                Catch ex As InvalidOperationException
                    Throw New ArgumentException(message:="User not found.", paramName:="username", innerException:=ex)
 
                End Try
 
            End Using ' searcher
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account name by SID.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim username As String = UserAccountUtil.FindUsername(sid:=New SecurityIdentifier("S-1-5-21-1780771175-1208154119-2269826705-500"))
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds the username of the specified security identifier (SID) in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="sid">
    ''' A <see cref="SecurityIdentifier"/> (SID) object.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' The username.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindUsername(ByVal sid As SecurityIdentifier) As String
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(sid)
 
            Return user.Name
 
        End Using
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account SID by username.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim sid As SecurityIdentifier = UserAccountUtil.FindSid(username:="Administrator"))
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds the security identifier (SID) of the specified username account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' A <see cref="SecurityIdentifier"/> (SID) object.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindSid(ByVal username As String) As SecurityIdentifier
 
        Return UserAccountUtil.FindUser(username).Sid
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account's profile path by username.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim profilePath As String = UserAccountUtil.FindProfilePath(username:="Administrator"))
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds the profile directory path of the specified username account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name to find.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' The profile directory path.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindProfilePath(ByVal userName As String) As String
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(userName)
 
            Return CStr(My.Computer.Registry.GetValue(String.Format("HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\ProfileList\{0}",
                                                                    user.Sid.Value),
                                                                    "ProfileImagePath", ""))
 
        End Using
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Find user-account's profile path by SID.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim profilePath As String = UserAccountUtil.FindProfilePath(sid:=New SecurityIdentifier("S-1-5-21-1780771175-1208154119-2269826705-500"))
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Finds the profile directory path of the specified username account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="sid">
    ''' A <see cref="SecurityIdentifier"/> (SID) object.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' The profile directory path.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function FindProfilePath(ByVal sid As SecurityIdentifier) As String
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(sid)
 
            Return CStr(My.Computer.Registry.GetValue(String.Format("HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\ProfileList\{0}",
                                                                    user.Sid.Value),
                                                                    "ProfileImagePath", ""))
 
        End Using
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : User is Admin?.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim userIsAdmin As Boolean = UserAccountUtil.IsAdmin(username:="Administrator")
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Determines whether an user-account of the current machine context is an Administrator.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' <c>True</c> if the user is an Administrator, otherwise, <c>False</c>.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function IsAdmin(ByVal username As String) As Boolean
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(username)
 
            Using group As GroupPrincipal = GroupPrincipal.FindByIdentity(user.Context, IdentityType.Sid, New SecurityIdentifier(WellKnownSidType.BuiltinAdministratorsSid, Nothing).Value)
 
                Return user.IsMemberOf(group)
 
            End Using ' group
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : User is member of group...?.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim userIsGuest As Boolean = UserAccountUtil.IsMemberOfGroup(username:="Administrator", groupSid:=WellKnownSidType.BuiltinGuestsSid)
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Determines whether an user-account of the current machine context is a member of the specified group.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' 
    ''' <param name="groupSid">
    ''' A <see cref="WellKnownSidType"/> security identifier (SID) that determines the account group.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' <c>True</c> if the user is a member of the specified group, otherwise, <c>False</c>.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function IsMemberOfGroup(ByVal username As String,
                                           ByVal groupSid As WellKnownSidType) As Boolean
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(username)
 
            Using group As GroupPrincipal = GroupPrincipal.FindByIdentity(user.Context, IdentityType.Sid, New SecurityIdentifier(groupSid, Nothing).Value)
 
                Return user.IsMemberOf(group)
 
            End Using ' group
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : User is member of group...?.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim userIsGuest As Boolean = UserAccountUtil.IsMemberOfGroup(username:="Administrator", groupname:="Guests")
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Determines whether an user-account of the current machine context is a member of the specified group.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' 
    ''' <param name="groupname">
    ''' The name of thehe group.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' <c>True</c> if the user is a member of the specified group, otherwise, <c>False</c>.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function IsMemberOfGroup(ByVal username As String,
                                           ByVal groupname As String) As Boolean
 
        Using user As UserPrincipal = UserAccountUtil.FindUser(username)
 
            Using group As GroupPrincipal = GroupPrincipal.FindByIdentity(user.Context, IdentityType.Name, groupname)
 
                Return user.IsMemberOf(group)
 
            End Using ' group
 
        End Using ' user
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Create user-account.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' Dim user as UserPrincipal = UserAccountUtil.Create(username:="Elektro",
    '''                                                    password:="",
    '''                                                    displayName:="Elektro Account.",
    '''                                                    description:="This is a test user-account.",
    '''                                                    canChangePwd:=True,
    '''                                                    pwdExpires:=False,
    '''                                                    groupSid:=WellKnownSidType.BuiltinAdministratorsSid)
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Creates a new user account in the current machine context.
    ''' This function does NOT adds a new user in the current machine.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' 
    ''' <param name="password">
    ''' The user password.
    ''' If this value is empty, account is set to don't require any password.
    ''' </param>
    ''' 
    ''' <param name="displayName">
    ''' The display name of the user account.
    ''' </param>
    ''' 
    ''' <param name="description">
    ''' The description of the user account.
    ''' </param>
    ''' 
    ''' <param name="canChangePwd">
    ''' A value that indicates whether the user can change its password.
    ''' </param>
    ''' 
    ''' <param name="pwdExpires">
    ''' A value that indicates whether the password should expire.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <returns>
    ''' An <see cref="UserPrincipal"/> object that contains the user data.
    ''' </returns>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Function Create(ByVal username As String,
                                  ByVal password As String,
                                  ByVal displayName As String,
                                  ByVal description As String,
                                  ByVal canChangePwd As Boolean,
                                  ByVal pwdExpires As Boolean) As UserPrincipal
 
        Using context As New PrincipalContext(ContextType.Machine)
 
            Dim user As New UserPrincipal(context)
 
            With user
 
                .Name = username
 
                .SetPassword(password)
                .PasswordNotRequired = String.IsNullOrEmpty(password)
 
                .DisplayName = displayName
                .Description = description
 
                .UserCannotChangePassword = canChangePwd
                .PasswordNeverExpires = pwdExpires
 
                .Enabled = True
                .Save()
 
            End With
 
            Return user
 
        End Using
 
    End Function
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Add user-account.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' UserAccountUtil.Add(username:="Elektro",
    '''                     password:="",
    '''                     displayName:="Elektro Account.",
    '''                     description:="This is a test user-account.",
    '''                     canChangePwd:=True,
    '''                     pwdExpires:=False,
    '''                     groupSid:=WellKnownSidType.BuiltinAdministratorsSid)
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Adds a new user account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name.
    ''' </param>
    ''' 
    ''' <param name="password">
    ''' The user password.
    ''' If this value is empty, account is set to don't require any password.
    ''' </param>
    ''' 
    ''' <param name="displayName">
    ''' The display name of the user account.
    ''' </param>
    ''' 
    ''' <param name="description">
    ''' The description of the user account.
    ''' </param>
    ''' 
    ''' <param name="canChangePwd">
    ''' A value that indicates whether the user can change its password.
    ''' </param>
    ''' 
    ''' <param name="pwdExpires">
    ''' A value that indicates whether the password should expire.
    ''' </param>
    ''' 
    ''' <param name="groupSid">
    ''' A <see cref="WellKnownSidType"/> security identifier (SID) that determines the account group where to add the user.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Sub Add(ByVal username As String,
                          ByVal password As String,
                          ByVal displayName As String,
                          ByVal description As String,
                          ByVal canChangePwd As Boolean,
                          ByVal pwdExpires As Boolean,
                          Optional ByVal groupSid As WellKnownSidType = WellKnownSidType.BuiltinUsersSid)
 
        Using context As New PrincipalContext(ContextType.Machine)
 
            Using user As UserPrincipal = UserAccountUtil.Create(username, password, displayName, description, canChangePwd, pwdExpires)
 
                Using group As GroupPrincipal = GroupPrincipal.FindByIdentity(context, IdentityType.Sid, New SecurityIdentifier(groupSid, Nothing).Value)
 
                    group.Members.Add(user)
                    group.Save()
 
                End Using ' group
 
            End Using ' user
 
        End Using ' context
 
    End Sub
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Add user-account.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' UserAccountUtil.Add(user:=myUserPrincipal, groupSid:=WellKnownSidType.BuiltinAdministratorsSid)
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Adds a new user account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="user">
    ''' An <see cref="UserPrincipal"/> object that contains the user data.
    ''' </param>
    '''
    ''' <param name="groupSid">
    ''' A <see cref="WellKnownSidType"/> security identifier (SID) that determines the account group where to add the user.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Sub Add(ByVal user As UserPrincipal,
                          Optional ByVal groupSid As WellKnownSidType = WellKnownSidType.BuiltinUsersSid)
 
        Using context As New PrincipalContext(ContextType.Machine)
 
            Using group As GroupPrincipal = GroupPrincipal.FindByIdentity(context, IdentityType.Sid, New SecurityIdentifier(groupSid, Nothing).Value)
 
                group.Members.Add(user)
                group.Save()
 
            End Using ' group
 
        End Using ' context
 
    End Sub
 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <remarks>
    ''' Title : Delete user-account.
    ''' Author: Elektro
    ''' Date  : 19-June-2015
    ''' </remarks> 
    ''' ----------------------------------------------------------------------------------------------------
    ''' <example>
    ''' UserAccountUtil.Delete(username:="User name")
    ''' </example>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <summary>
    ''' Deletes an user account in the current machine context.
    ''' </summary>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <param name="username">
    ''' The user name of the user-account to delete.
    ''' </param>
    ''' ----------------------------------------------------------------------------------------------------
    ''' <exception cref="ArgumentException">
    ''' User not found.;username
    ''' </exception>
    ''' ----------------------------------------------------------------------------------------------------
    <DebuggerStepThrough>
    Public Shared Sub Delete(ByVal username As String)
 
        Using curUser As UserPrincipal = UserAccountUtil.FindUser(username)
 
            curUser.Delete()
 
        End Using
 
    End Sub
 
#End Region
 
End Class
 

  Public Function DecaBin(numero As Integer) As String
        If numero <= 2 Then 'Caso Base
            DecaBin = (numero \ 2) & (numero Mod 2)
        Else 'Caso Recursivo
            DecaBin = DecaBin(numero \ 2) & numero Mod 2
        End If
    End Function
 
 
# ejemplo de uso
 
 Textbox = DecaBin(numeromio)

    Sub Test()
 
        ' Restart the current computer in 30 seconds and wait for applications to close.
        ' Specify that the restart operation is planned because a consecuence of an installation.
        Dim success As Boolean =
            SystemRestarter.Restart("127.0.0.1", 30, "System is gonna be restarted quickly, go save all your data now...!",
                                    SystemRestarter.ShutdownMode.Wait,
                                    SystemRestarter.ShutdownReason.MajorOperatingSystem Or
                                    SystemRestarter.ShutdownReason.MinorInstallation,
                                    SystemRestarter.ShutdownPlanning.Planned)
 
        Console.WriteLine(String.Format("Restart operation initiated successfully?: {0}", CStr(success)))
 
        ' Abort the current operation.
        If success Then
            Dim isAborted As Boolean = SystemRestarter.Abort()
            Console.WriteLine(String.Format("Restart operation aborted   successfully?: {0}", CStr(isAborted)))
        Else
            Console.WriteLine("There is any restart operation to abort.")
        End If
        Console.ReadKey()
 
        ' Shutdown the current computer instantlly and force applications to close.
        ' ( When timeout is '0' the operation can't be aborted )
        SystemRestarter.Shutdown(Nothing, 0, Nothing, SystemRestarter.ShutdownMode.ForceSelf)
 
        ' LogOffs the current user.
        SystemRestarter.LogOff(SystemRestarter.LogOffMode.Wait)
 
    End Sub

Private Shared ReadOnly privilegeNameOfShutdown As String = "SeRemoteShutdownPrivilege"
Private Shared ReadOnly privilegeNameOfRemoteShutdown As String = "SeRemoteShutdownPrivilege"