vb中從域名得到IP及從IP得到域名 (轉)

vb中從域名得到IP及從IP得到域名 (轉)[@more@]

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 WYS_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 gethostbyaddr Lib "WSOCK32.DLL" (addr As Any, ByVal _
byteslen As Integer, addrtype As Integer) As Long
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 hpv&, ByVal cbCopy&)

Function hibyte(ByVal wParam As Integer)  '獲得整數的高位
  hibyte = wParam &H100 And &HFF&
End Function

Function lobyte(ByVal wParam As Integer)  '獲得整數的低位
  lobyte = wParam And &HFF&
End Function

Function 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 沒有反應."
  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 = " Sockets版本 " & sLowByte & "." & sHighByte
  sMsg = sMsg & " 不被winsock.dll支援 "
  MsgBox sMsg
  End
  End If
 
  If WSAD.iMaxSockets < MIN_SOCKETS_REQD Then
  sMsg = "這個需要的最少Sockets數為 "
  sMsg = sMsg & Trim$(str$(MIN_SOCKETS_REQD))
  MsgBox sMsg
  End
  End If
 
End Function

Sub SocketsCleanup()
  Dim lReturn As Long
 
  lReturn = WSACleanup()
 
  If lReturn <> 0 Then
  MsgBox "Socket錯誤 " & 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 Function getip(name As String) As String
  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(name)
 
  If hostent_addr = 0 Then
  get= ""  '主機名不能被解釋
  Exit Function
  End If
 
  RtlMoveMemory host, hostent_addr, LenB(host)
  RtlMoveMemory hostip_addr, host.hAddrList, 4
 
  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)
 
  getip = ip_address

End Function

Private Sub Command1_click()
  Dim str As String
  str = getip(Text1.Text)
  If str = "" Then
  Text2.Text = "主機名不能被解釋"
  Else
  Text2.Text = str
  End If
End Sub
Private Function getname(addrstr As String) As String
  Dim hostent_addr As Long
  Dim host As HOSTENT
  Dim addr(0 To 50) As Byte
  Dim addrs As String
  Dim hname(1 To 50) As Byte
  Dim str As String
  Dim i As Integer, j As Integer
  Dim temp_int As Integer
  Dim byt As Byte
  str = Trim$(addrstr)
  i = 0
  j = 0
  Do
  temp_int = 0
  i = i + 1
  Do While Mid$(str, i, 1) >= "0" And Mid$(str, i, 1) <= "9" And i <= Len(str)
  temp_int = temp_int * 10 + Mid$(str, i, 1)
  i = i + 1
  L
  If temp_int <= 255 Then
  addr(j) = temp_int
  j = j + 1
  End If
 
  Loop Until Mid$(str, i, 1) <> "." Or i > Len(str) Or temp_int > 255
  If temp_int > 255 Then
  getname = "地址"
  Exit Function
  End If
  hostent_addr = gethostbyaddr(addr(0), j, 2)
  If hostent_addr = 0 Then
  getname = "此地址無法解析"
  Exit Function
  End If
  RtlMoveMemory host, hostent_addr, LenB(host)
  RtlMoveMemory hname(1), host.hname, 50
  j = 51
  For i = 1 To 50
  If hname(i) = 0 Then
  j = i
  End If
  If i >= j Then
  hname(i) = 32
  End If
  Next i
  getname = Trim$(StrConv(hname, vbUnicode))
End Function
Private Sub Command2_Click()
  Dim name As String
  name = getname(Text2.Text)
  If name = "" Then
  name = "此地址沒有域名"
  End If
  Text1.Text = name
End Sub