如何获得本地计算机的IP地址
编号：QA000616
建立日期: 1999年3月9日 最后修改日期：2002年3月25日
所属类别：
Chees:
VB5 (sp3)
Win98
当我使用VB5.0编程时，我如何获得我的计算机的IP地址？使用哪个API?
回答:
应该调用WinSock的几个函数。先使用gethostname获得本机的名字，然后使用gethostbyname得到IP地址。下面的例子摘自微软的Knowledge Base的文章：“Q160215 OWTO: Obtain the Host IP Address Using Windows Sockets”。
1. 启动Visual Basic，将建立Form1。
2. 放置按钮Command1在Form1上。
3. 在 Form1的声明部分放置如下代码:
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&, 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&)
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
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
Sub Form_Load()
SocketsInitialize
End Sub
Private Sub Form_Unload(Cancel As Integer)
SocketsCleanup
End Sub
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$(hostname)
End If
hostent_addr = gethostbyname(hostname)
If hostent_addr = 0 Then
MsgBox "Winsock.dll is not responding."
Exit Sub
End If
RtlMoveMemory host, hostent_addr, LenB(host)
RtlMoveMemory hostip_addr, host.hAddrList, 4
MsgBox hostname
'get all of the IP address if machine is multi-homed
Do
ReDim temp_ip_address(1 To host.hLength)
RtlMoveMemory temp_ip_address(1), hostip_addr, host.hLength
For i = 1 To host.hLength
ip_address = ip_address & temp_ip_address(i) & "."
Next
ip_address = Mid$(ip_address, 1, Len(ip_address) - 1)
MsgBox ip_address
ip_address = ""
host.hAddrList = host.hAddrList + LenB(host.hAddrList)
RtlMoveMemory hostip_addr, host.hAddrList, 4
Loop While (hostip_addr <> 0)
End Sub
4. 按F5键运行程序。
5. 点击Command1获得主机信息。
Forever的意见：
你只要用一个Winsock控件然后读它的LocalIP就可以返回你主机的IP地址。
此问题由李海回答。
| |
|
|
| |
|
|
