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 gethostbyname Lib "WSOCK32.DLL" (ByVal _
hostname$) As Long
Private Declare Sub RtlMoveMemory Lib "KERNEL32" (hpvDest As Any, _
ByVal hpvSource&, ByVal cbCopy&)
Function hibyte(ByVal wParam As Integer) '获得整数的高位
hibyte = wParam \ &H100 And &HFF&
End Function
Function lobyte(ByVal wParam As Integer) '获得整数的低位
lobyte = wParam And &HFF&
End Function
Sub SocketsInitialize()
Dim WSAD As WSADATA
Dim iReturn As Integer
Dim sLowByte As String, sHighByte As String, sMsg As String
iReturn = WSAStartup(WS_VERSION_REQD, WSAD)
If iReturn <> 0 Then
MsgBox "Winsock.dll 没有反应."
End
End If
If lobyte(WSAD.wversion) < WS_VERSION_MAJOR Or (lobyte(WSAD.wversion) = WS_VERSION_MAJOR And hibyte(WSAD.wversion) < WS_VERSION_MINOR) Then
sHighByte = Trim$(Str$(hibyte(WSAD.wversion)))
sLowByte = Trim$(Str$(lobyte(WSAD.wversion)))
sMsg = "Windows Sockets版本 " & sLowByte & "." & sHighByte
sMsg = sMsg & " 不被winsock.dll支持 "
MsgBox sMsg
End
End If
If WSAD.iMaxSockets < MIN_SOCKETS_REQD Then
sMsg = "这个系统需要的最少Sockets数为 "
sMsg = sMsg & Trim$(Str$(MIN_SOCKETS_REQD))
MsgBox sMsg
End
End If
End Sub
Sub SocketsCleanup()
Dim lReturn As Long
lReturn = WSACleanup()
If lReturn <> 0 Then
MsgBox "Socket错误 " & Trim$(Str$(lReturn)) & " occurred in Cleanup "
End
End If
End Sub
Sub Form_Load()
'初始化Socket
SocketsInitialize
End Sub
Private Sub Form_Unload(Cancel As Integer)
'清除Socket
SocketsCleanup
End Sub
Private Sub Command1_click()
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
hostent_addr = gethostbyname(Text1)
If hostent_addr = 0 Then
MsgBox "主机名不能被解释."
Exit Sub
End If