使用VB截获WIN98系列下的IP数据包

ent = CreateEvent(0, 1, 0, vbNullString)
        If (hEvent = 0) Then
            MsgBox "ERROR CREATEEVENT"
            RecvPacket = SYSERR
            Exit Function
        End If
        RecvTab(K).hEvent = hEvent
        ''memset(RecvTab[k].Buffer,0,BUFFER_SIZE);
        RecvTab(K).Size = BUFFER_SIZE
        RecvTab(K).Active = True
        RecvTab(K).Type = nREAD
        EventTab(RECV_MAX - 1) = hEvent
        Call RecvStart(hVxD, RecvTab(K))
        RecvPacket = len1
        Exit Function
    Else
        RecvPacket = SYSERR
    End If
End Function


Function RecvStart(ByVal hVxD As Long, packtab As PacketTable) As Long
    Dim result As Long
    packtab.Overlap.Internal = 0
    packtab.Overlap.InternalHigh = 0
    packtab.Overlap.offset = 0
    packtab.Overlap.OffsetHigh = 0
    packtab.Overlap.hEvent = packtab.hEvent

    result = DeviceIoControl(hVxD, _
                           IOCTL_PROTOCOL_READ, _
                           packtab.Buffer(0), _
                           packtab.Size, _
                           packtab.Buffer(0), _
                           packtab.Size, _
                           packtab.Length, _
                           packtab.Overlap)

    If (result <> 0)