'Projeye eklenmesi gerekenler:
' 2 adet textbox ve 1 adet buton

Option Explicit

Private Const NO_ERROR = 0

Private Declare Function inet_addr Lib "wsock32.dll" _
(ByVal s As String) As Long

Private Declare Function SendARP Lib "iphlpapi.dll" _
(ByVal DestIP As Long, _
ByVal SrcIP As Long, _
pMacAddr As Long, _
PhyAddrLen As Long) As Long

Private Declare Sub CopyMemory Lib "kernel32" _
Alias "RtlMoveMemory" _
(dst As Any, _
src As Any, _
ByVal bcount As Long)



Private Sub Form_Load()

Text1.Text = "192.168.1.101"
Text2.Text = ""
Command1.Caption = "Get Remote Mac Address"

End Sub


Private Sub Command1_Click()

Dim sRemoteMacAddress As String

If Len(Text1.Text) > 0 Then

If GetRemoteMACAddress(Text1.Text, sRemoteMacAddress) Then
Text2.Text = sRemoteMacAddress
Else
Text2.Text = "(SendARP call failed)"
End If

End If

End Sub


Private Function GetRemoteMACAddress(ByVal sRemoteIP As String, _
sRemoteMacAddress As String) As Boolean

Dim dwRemoteIP As Long
Dim pMacAddr As Long
Dim bpMacAddr() As Byte
Dim PhyAddrLen As Long
Dim cnt As Long
Dim tmp As String

'convert the string IP into
'an unsigned long value containing
'a suitable binary representation
'of the Internet address given
dwRemoteIP = inet_addr(sRemoteIP)

If dwRemoteIP <> 0 Then

'set PhyAddrLen to 6
PhyAddrLen = 6

'retrieve the remote MAC address
If SendARP(dwRemoteIP, 0&, pMacAddr, PhyAddrLen) = NO_ERROR Then

If pMacAddr <> 0 And PhyAddrLen <> 0 Then

'returned value is a long pointer
'to the mac address, so copy data
'to a byte array
ReDim bpMacAddr(0 To PhyAddrLen - 1)
CopyMemory bpMacAddr(0), pMacAddr, ByVal PhyAddrLen

'loop through array to build string
For cnt = 0 To PhyAddrLen - 1

If bpMacAddr(cnt) = 0 Then
tmp = tmp & "00-"
Else
tmp = tmp & Hex$(bpMacAddr(cnt)) & "-"
End If

Next

'remove the trailing dash
'added above and return True
If Len(tmp) > 0 Then
sRemoteMacAddress = Left$(tmp, Len(tmp) - 1)
GetRemoteMACAddress = True
End If

Exit Function

Else
GetRemoteMACAddress = False
End If

Else
GetRemoteMACAddress = False
End If 'SendARP

Else
GetRemoteMACAddress = False
End If 'dwRemoteIP

End Function