[pr0sper0]

Código Delphi [-]
Option Explicit

Const RAS95_MaxEntryName = 256


Private Type RASENTRYNAME95
    dwSize As Long
    szEntryName(RAS95_MaxEntryName) As Byte
End Type


Private Type RASDIALPARAMS
    dwSize As Long
    szEntryName As String * 257
    szPhoneNumber As String * 129
    szCallbackNumber As String * 129
    szUserName As String * 257
    szPassword As String * 257
    szDomain As String * 16
    filler As String * 16
End Type


Private Declare Function RasEnumEntries Lib "rasapi32.dll" Alias "RasEnumEntriesA" _
    (ByVal reserved As String, _
     ByVal lpszPhonebook As String, _
     lprasentryname As Any, _
     lpcb As Long, _
     lpcEntries As Long) As Long
 

Private Type RASCONN
    dwSize As Long
    hRasConn As Long
    szEntryName(0 To 256) As Byte
    szDeviceType(0 To 16) As Byte
    szDeviceName(0 To 128) As Byte
    pad As Byte
End Type


Private Declare Function RasEnumConnections Lib "rasapi32" Alias "RasEnumConnectionsA" ( _
    ByVal lprasconn As Long, _
    ByVal lpcb As Long, _
    ByVal lpcConnections As Long) As Long



Private Declare Sub Sleep Lib "kernel32.dll" (ByVal miliseg As Long)

Private Declare Sub strcpyn Lib "kernel32.dll" Alias "lstrcpynA" _
    (ByVal a As String, _
     ByVal de As String, _
     ByVal N As Long)

Private Declare Function strlen Lib "kernel32.dll" Alias "lstrlenA" _
    (ByVal texto As String) As Long

Private Declare Function RasHangUp Lib "rasapi32.dll" Alias "RasHangUpA" _
    (ByVal handle As Long) As Integer

Private Declare Function RasDial Lib "rasapi32.dll" Alias "RasDialA" _
    (ByVal p1 As Long, _
     ByVal p2 As Long, _
     rd As RASDIALPARAMS, _
     ByVal p4 As Long, _
     ByVal p5 As Long, _
     handle As Long) As Integer

Private Declare Sub RasGetErrorString Lib "rasapi32.dll" Alias "RasGetErrorStringA" _
    (ByVal nmumer As Long, _
     ByVal buffer As String, _
     ByVal sizebuf As Long)

Private Declare Function InternetGetConnectedState Lib "wininet.dll" ( _
    ByRef lpdwFlags As Long, _
    ByVal dwReserved As Long) As Long

Dim hDial As Long

Function Conectar(Entry As String, _
                  User As String, _
                  Pass As String) As Integer

Dim Rdp As RASDIALPARAMS
    
    Rdp.dwSize = 1052
    
    strcpyn Rdp.szEntryName, Entry + Chr$(0), 256
    strcpyn Rdp.szPhoneNumber, Chr$(0), 128
    strcpyn Rdp.szCallbackNumber, Chr$(0), 128
    strcpyn Rdp.szUserName, User + Chr$(0), 256
    strcpyn Rdp.szPassword, Pass + Chr$(0), 256
    strcpyn Rdp.szDomain, Chr$(0), 15


    Conectar = RasDial(0, 0, Rdp, 0, 0, hDial)

End Function


Function Desconectar() As Long
Dim N As Long

        N = RasHangUp(hDial)
        hDial = GetHandleConnection
        Sleep (3000)
        Desconectar = N

End Function

Function TextoError(Num As Long) As String
Dim Txt As String * 128

    Txt = Chr$(0)
    RasGetErrorString Num, Txt, 127
    TextoError = Left$(Txt, strlen(Txt))

End Function
Private Sub Command1_Click()
Dim N As Long
    
    Me.MousePointer = vbHourglass
    
    If IsOnline = False Then
        MsgBox "Ya se estaba conectado a internet", vbInformation
    Else
        N = Conectar(List1, Text1, Text2)
        If N = 0 Then
            MsgBox "Conectado a internet", vbInformation
        Else
            MsgBox TextoError(N), vbCritical
        End If
     End If
     
     Me.MousePointer = 0
     
End Sub

Private Sub Command2_Click()

Dim N As Long
    
    Me.MousePointer = vbHourglass
    
    hDial = GetHandleConnection
    
    If IsOnline = False Then
        MsgBox "No se estaba conectado a internet", vbExclamation
    Else
        N = Desconectar
        If N = 0 Then
           MsgBox "Desconectado", vbInformation
        Else
           MsgBox TextoError(N), vbCritical, "Mensaje de error"
        End If
    End If
    
    hDial = GetHandleConnection
    Me.MousePointer = 0
End Sub


Private Sub ListarConexiones()

Dim s As Long, l As Long, ln As Long, a$
ReDim r(255) As RASENTRYNAME95

    r(0).dwSize = 264
    s = 256 * r(0).dwSize
    l = RasEnumEntries(vbNullString, vbNullString, r(0), s, ln)
    
    For l = 0 To ln - 1
        a$ = StrConv(r(l).szEntryName(), vbUnicode)
        List1.AddItem Left$(a$, InStr(a$, Chr$(0)) - 1)
    Next
    
    If List1.ListCount > 0 Then
        List1.ListIndex = 0
    End If
    hDial = GetHandleConnection
End Sub

Function GetHandleConnection() As Long
    Dim conn As RASCONN
    Dim y As Long, z As Long
    Dim ret As Long
    conn.dwSize = Len(conn)
    y = conn.dwSize
    ret = RasEnumConnections(VarPtr(conn), _
                             VarPtr(y), _
                             VarPtr(z))
    
    GetHandleConnection = conn.hRasConn
    
End Function
Public Function IsOnline() As Boolean
   IsOnline = InternetGetConnectedState(0&, 0&)
End Function


Private Sub Form_Load()
Text1.Visible = False
Text2.Visible = False
    Call ListarConexiones

    Me.Caption = " Acceso RAS, " & _
                 "conectar y desconectar"
    Command1.Caption = "Conectar"
    Command2.Caption = "Desconectar"
End Sub