How do I get the IP address of a machine using VB6 code?
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How do I get the IP address of a machine using VB6 code?
You can use:
vb Code:
Text1.Text = winsock.RemoteHostIP
Although, how are you going to connect to the remote machine in the first place?
The reality isn't so simple.
An individual computer can have multiple adapters and each adapter can have multiple IP addresses. Which of these N * M addresses gets returned by the Winsock control depends on what actions have been performed on the control first (such as an action that specified which IP address to use).
In the degenerate case you'll usually get the first (i.e. "preferred") one though, and in the extreme degenerate case of John Doe's home PC there is only one anyway.
This is changing though. As more John Does out there start running VM software they'll find they have software adapters installed on their machines for bridging to VMs.
But the funny part is, none of this may relate to the question that is trying to be asked here anyway. After all, knowing "your IP address" is generally pretty useless since you can use the loopback address for local operations.
I suspect the OP here may be asking how to find his router's public IP address.
Well I will clarify. The situation is something like this.
My company has some 200 branches with some 1200 machines connected on a WAN. The Head Office will send periodical statements to the branches. When a statement arrives, a window will pop up on the branch machine and the user has to click a button. On clicking the button a message will be sent to the machine at Head Office which should contain the IP address of the machine. I hope it is clear now. :)
Well then did the simple Winsock control approach resolve the question?
If so you can mark this revolved via the Thread Tools menu above.
That being the situation I might suggest the following, knowing the IP could change and it sounds like you want proof that a specific machine clicked ok. (e.g. IP addresses can/will probably change. DHCP and all...)
Assuming the machine name would suffice you could easily use something like this.....
vb Code:
Private Sub Command1_Click() Dim strMachineName As String strMachineName = Environ$("COMPUTERNAME") ' Send your message here End Sub
I knew I had this code some where. I do not recall where I picked this up, I am not the author.
So, just in case you MUST have the IP address.....
vb Code:
Option Explicit Public Const MAX_WSADescription As Long = 256 Public Const MAX_WSASYSStatus As Long = 128 Public Const ERROR_SUCCESS As Long = 0 Public Const WS_VERSION_REQD As Long = &H101 Public Const WS_VERSION_MAJOR As Long = WS_VERSION_REQD \ &H100 And &HFF& Public Const WS_VERSION_MINOR As Long = WS_VERSION_REQD And &HFF& Public Const MIN_SOCKETS_REQD As Long = 1 Public Const SOCKET_ERROR As Long = -1 Public Type HOSTENT hName As Long hAliases As Long hAddrType As Integer hLen As Integer hAddrList As Long End Type Public Type WSADATA wVersion As Integer wHighVersion As Integer szDescription(0 To MAX_WSADescription) As Byte szSystemStatus(0 To MAX_WSASYSStatus) As Byte wMaxSockets As Integer wMaxUDPDG As Integer dwVendorInfo As Long End Type Public Declare Function WSAGetLastError Lib "wsock32" () As Long Public Declare Function WSAStartup Lib "wsock32" _ (ByVal wVersionRequired As Long, _ lpWSADATA As WSADATA) As Long Public Declare Function WSACleanup Lib "wsock32" () As Long Public Declare Function gethostname Lib "wsock32" _ (ByVal szHost As String, _ ByVal dwHostLen As Long) As Long Public Declare Function gethostbyname Lib "wsock32" _ (ByVal szHost As String) As Long Public Declare Sub CopyMemory Lib "kernel32" _ Alias "RtlMoveMemory" _ (hpvDest As Any, _ ByVal hpvSource As Long, _ ByVal cbCopy As Long) Public Function GetIPAddress() As String Dim sHostName As String * 256 Dim lpHost As Long Dim HOST As HOSTENT Dim dwIPAddr As Long Dim tmpIPAddr() As Byte Dim i As Integer Dim sIPAddr As String If Not SocketsInitialize() Then GetIPAddress = "" Exit Function End If 'gethostname returns the name of the local host into 'the buffer specified by the name parameter. The host 'name is returned as a null-terminated string. The 'form of the host name is dependent on the Windows 'Sockets provider - it can be a simple host name, or 'it can be a fully qualified domain name. However, it 'is guaranteed that the name returned will be successfully 'parsed by gethostbyname and WSAAsyncGetHostByName. 'In actual application, if no local host name has been 'configured, gethostname must succeed and return a token 'host name that gethostbyname or WSAAsyncGetHostByName 'can resolve. If gethostname(sHostName, 256) = SOCKET_ERROR Then GetIPAddress = "" MsgBox "Windows Sockets error " & Str(WSAGetLastError()) & _ " has occurred. Unable to successfully get Host Name." SocketsCleanup Exit Function End If 'gethostbyname returns a pointer to a HOSTENT structure '- a structure allocated by Windows Sockets. The HOSTENT 'structure contains the results of a successful search 'for the host specified in the name parameter. 'The application must never attempt to modify this 'structure or to free any of its components. Furthermore, 'only one copy of this structure is allocated per thread, 'so the application should copy any information it needs 'before issuing any other Windows Sockets function calls. 'gethostbyname function cannot resolve IP address strings 'passed to it. Such a request is treated exactly as if an 'unknown host name were passed. Use inet_addr to convert 'an IP address string the string to an actual IP address, 'then use another function, gethostbyaddr, to obtain the 'contents of the HOSTENT structure. sHostName = Trim$(sHostName) lpHost = gethostbyname(sHostName) If lpHost = 0 Then GetIPAddress = "" MsgBox "Windows Sockets are not responding. " & _ "Unable to successfully get Host Name." SocketsCleanup Exit Function End If 'to extract the returned IP address, we have to copy 'the HOST structure and its members CopyMemory HOST, lpHost, Len(HOST) CopyMemory dwIPAddr, HOST.hAddrList, 4 'create an array to hold the result ReDim tmpIPAddr(1 To HOST.hLen) CopyMemory tmpIPAddr(1), dwIPAddr, HOST.hLen 'and with the array, build the actual address, 'appending a period between members For i = 1 To HOST.hLen sIPAddr = sIPAddr & tmpIPAddr(i) & "." Next 'the routine adds a period to the end of the 'string, so remove it here GetIPAddress = Mid$(sIPAddr, 1, Len(sIPAddr) - 1) SocketsCleanup End Function Public Function GetIPHostName() As String Dim sHostName As String * 256 If Not SocketsInitialize() Then GetIPHostName = "" Exit Function End If If gethostname(sHostName, 256) = SOCKET_ERROR Then GetIPHostName = "" MsgBox "Windows Sockets error " & Str(WSAGetLastError()) & _ " has occurred. Unable to successfully get Host Name." SocketsCleanup Exit Function End If GetIPHostName = Left$(sHostName, InStr(sHostName, Chr(0)) - 1) SocketsCleanup End Function Public Function HiByte(ByVal wParam As Integer) As Byte 'note: VB4-32 users should declare this function As Integer HiByte = (wParam And &HFF00&) \ (&H100) End Function Public Function LoByte(ByVal wParam As Integer) As Byte 'note: VB4-32 users should declare this function As Integer LoByte = wParam And &HFF& End Function Public Sub SocketsCleanup() If WSACleanup() <> ERROR_SUCCESS Then MsgBox "Socket error occurred in Cleanup." End If End Sub Public Function SocketsInitialize() As Boolean Dim WSAD As WSADATA Dim sLoByte As String Dim sHiByte As String If WSAStartup(WS_VERSION_REQD, WSAD) <> ERROR_SUCCESS Then MsgBox "The 32-bit Windows Socket is not responding." SocketsInitialize = False Exit Function End If If WSAD.wMaxSockets < MIN_SOCKETS_REQD Then MsgBox "This application requires a minimum of " & _ CStr(MIN_SOCKETS_REQD) & " supported sockets." SocketsInitialize = False Exit Function End If If LoByte(WSAD.wVersion) < WS_VERSION_MAJOR Or _ (LoByte(WSAD.wVersion) = WS_VERSION_MAJOR And _ HiByte(WSAD.wVersion) < WS_VERSION_MINOR) Then sHiByte = CStr(HiByte(WSAD.wVersion)) sLoByte = CStr(LoByte(WSAD.wVersion)) MsgBox "Sockets version " & sLoByte & "." & sHiByte & _ " is not supported by 32-bit Windows Sockets." SocketsInitialize = False Exit Function End If 'must be OK, so lets do it SocketsInitialize = True End Function