|
|
|
|
|
Dicas
|
|
Visual Basic (Redes/Comunicações)
|
|
|
Título da Dica: Retornar o IP e o Host da maquina
|
|
|
|
Postada em 9/9/2003 por Ð@®l@n
Este artigo demonstra como obter o Host e o endereço IP de uma máquina local usando o GetHostByName API, utilizando DLL e soquetes do Windows, a Wsock32.dll. Para Obter os dois, utilize o GetHostByName conjuntamente com GetHostName.
GetHostName retorna o nome do Host Padrão de uma máquina local. Inicie um projeto, no formulário, adicione um commandButton. Na seção Option Explicit, adicione o seguinte código:
Private Const WS_VERSION_REQD = &H101 Private Const WS_VERSION_MAJOR = WS_VERSION_REQD \ &H100 And &HFF& Private Const WS_VERSION_MINOR = WS_VERSION_REQD And &HFF& Private Const MIN_SOCKETS_REQD = 1 Private Const SOCKET_ERROR = -1 Private Const WSADescription_Len = 256 Private Const WSASYS_Status_Len = 128
Private Type HOSTENT hName As Long hAliases As Long hAddrType As Integer hLength As Integer hAddrList As Long End Type
Private Type WSADATA wversion As Integer wHighVersion As Integer szDescription(0 To WSADescription_Len) As Byte szSystemStatus(0 To WSASYS_Status_Len) As Byte iMaxSockets As Integer iMaxUdpDg As Integer lpszVendorInfo As Long End Type
Private Declare Function WSAGetLastError Lib "WSOCK32.DLL" () As Long
Private Declare Function WSAStartup Lib "WSOCK32.DLL" (ByVal wVersionRequired As Integer, lpWSAData As WSADATA) As Long
Private Declare Function WSACleanup Lib "WSOCK32.DLL" () As Long
Private Declare Function gethostname Lib "WSOCK32.DLL" (ByVal hostname$, ByVal HostLen As Long) As Long
Private Declare Function gethostbyname Lib "WSOCK32.DLL" (ByVal hostname$) As Long
Private Declare Sub RtlMoveMemory Lib "KERNEL32" (hpvDest As Any, ByVal hpvSource&, ByVal cbCopy&)
'Adicione as seguintes Functions:
Function hibyte(ByVal wParam As Integer) hibyte = wParam \ &H100 And &HFF& End Function
Function lobyte(ByVal wParam As Integer) lobyte = wParam And &HFF& End Function
'Insira as seguintes Sub:
Sub SocketsInitialize() Dim WSAD As WSADATA Dim iReturn As Integer Dim sLowByte As String, sHighByte As String, sMsg As String
iReturn = WSAStartup(WS_VERSION_REQD, WSAD)
If iReturn <> 0 Then MsgBox "Winsock.dll is not responding." End End If
If lobyte(WSAD.wversion) < WS_VERSION_MAJOR Or (lobyte(WSAD.wversion) = _ WS_VERSION_MAJOR And hibyte(WSAD.wversion) < WS_VERSION_MINOR) Then sHighByte = Trim$(Str$(hibyte(WSAD.wversion))) sLowByte = Trim$(Str$(lobyte(WSAD.wversion))) sMsg = "Windows Sockets version " & sLowByte & "." & sHighByte sMsg = sMsg & " is not supported by winsock.dll " MsgBox sMsg End End If
'iMaxSockets is not used in winsock 2. So the following check is only 'necessary for winsock 1. If winsock 2 is requested, 'the following check can be skipped.
If WSAD.iMaxSockets < MIN_SOCKETS_REQD Then sMsg = "This application requires a minimum of " sMsg = sMsg & Trim$(Str$(MIN_SOCKETS_REQD)) & " supported sockets." MsgBox sMsg End End If
End Sub
Sub SocketsCleanup() Dim lReturn As Long
lReturn = WSACleanup()
If lReturn <> 0 Then MsgBox "Socket error " & Trim$(Str$(lReturn)) & " occurred in Cleanup " End End If
End Sub
'No evento Load do formulário insira o seguinte código:
Sub Form_Load() SocketsInitialize End Sub
'E no evento UnLoad:
Private Sub Form_Unload(Cancel As Integer) SocketsCleanup End Sub
'Para finalizar, clique duas vezes no botão e adicione o seguinte código para o evento Click do botão:
Private Sub Command1_click() Dim hostname As String * 256 Dim hostent_addr As Long Dim host As HOSTENT Dim hostip_addr As Long Dim temp_ip_address() As Byte Dim i As Integer Dim ip_address As String
If gethostname(hostname, 256) = SOCKET_ERROR Then MsgBox "Windows Sockets error " & Str(WSAGetLastError()) Exit Sub Else hostname = Trim$(hostname) End If
hostent_addr = gethostbyname(hostname)
If hostent_addr = 0 Then MsgBox "Winsock.dll is not responding." Exit Sub End If
RtlMoveMemory host, hostent_addr, LenB(host) RtlMoveMemory hostip_addr, host.hAddrList, 4 MsgBox hostname, , "O Host é"
'get all of the IP address if machine is multi-homed
Do ReDim temp_ip_address(1 To host.hLength) RtlMoveMemory temp_ip_address(1), hostip_addr, host.hLength
For i = 1 To host.hLength ip_address = ip_address & temp_ip_address(i) & "." Next ip_address = Mid$(ip_address, 1, Len(ip_address) - 1)
MsgBox ip_address, , "O IP é:"
ip_address = "" host.hAddrList = host.hAddrList + LenB(host.hAddrList) RtlMoveMemory hostip_addr, host.hAddrList, 4 Loop While (hostip_addr <> 0) End Sub
|
|
|
|
|