[DllImport("iphlpapi.dll", EntryPoint="GetIpNetTable")]
static extern int GetIpNetTable(IntPtr pIpNetTable, ref int pdwSize, bool bOrder);
// Define the MIB_IPNETROW structure.
[StructLayout(LayoutKind.Sequential)]
struct MIB_IPNETROW
{
[MarshalAs(UnmanagedType.U4)]
public int dwIndex;
[MarshalAs(UnmanagedType.U4)]
public int dwPhysAddrLen;
[MarshalAs(UnmanagedType.U1)]
public byte mac0;
[MarshalAs(UnmanagedType.U1)]
public byte mac1;
[MarshalAs(UnmanagedType.U1)]
public byte mac2;
[MarshalAs(UnmanagedType.U1)]
public byte mac3;
[MarshalAs(UnmanagedType.U1)]
public byte mac4;
[MarshalAs(UnmanagedType.U1)]
public byte mac5;
[MarshalAs(UnmanagedType.U1)]
public byte mac6;
[MarshalAs(UnmanagedType.U1)]
public byte mac7;
[MarshalAs(UnmanagedType.U4)]
public int dwAddr;
[MarshalAs(UnmanagedType.U4)]
public int dwType;
}
Do you know one? Please contribute it!
If you are only interesting in getting the mac Address and you are deploying to Windows 2008 or later, you might want to use ResolveIpNetEntry2 (http://msdn.microsoft.com/en-us/library/aa814455(VS.85).aspx) instead.
Please add some!
//http://stackoverflow.com/questions/1148778/how-do-i-access-arp-protocol-information-through-c-net
using System;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Net;
namespace GetIpNetTable
{
class Program {
// The max number of physical addresses.
const int MAXLEN_PHYSADDR = 8;
// Declare the GetIpNetTable function.
[DllImport("IpHlpApi.dll")]
[return: MarshalAs(UnmanagedType.U4)]
static extern int GetIpNetTable(
IntPtr pIpNetTable,
[MarshalAs(UnmanagedType.U4)]
ref int pdwSize,
bool bOrder);
// The insufficient buffer error.
const int ERROR_INSUFFICIENT_BUFFER = 122;
static void Main(string[] args)
{
// The number of bytes needed.
int bytesNeeded = 0;
// The result from the API call.
int result = GetIpNetTable(IntPtr.Zero, ref bytesNeeded, false);
// Call the function, expecting an insufficient buffer.
if (result != ERROR_INSUFFICIENT_BUFFER)
{
// Throw an exception.
throw new Win32Exception(result);
}
// Allocate the memory, do it in a try/finally block, to ensure
// that it is released.
IntPtr buffer = IntPtr.Zero;
// Try/finally.
try
{
// Allocate the memory.
buffer = Marshal.AllocCoTaskMem(bytesNeeded);
// Make the call again. If it did not succeed, then
// raise an error.
result = GetIpNetTable(buffer, ref bytesNeeded, false);
// If the result is not 0 (no error), then throw an exception.
if (result != 0)
{
// Throw an exception.
throw new Win32Exception(result);
}
// Now we have the buffer, we have to marshal it. We can read
// the first 4 bytes to get the length of the buffer.
int entries = Marshal.ReadInt32(buffer);
// Increment the memory pointer by the size of the int.
IntPtr currentBuffer = new IntPtr(buffer.ToInt64() +
Marshal.SizeOf(typeof(int)));
// Allocate an array of entries.
MIB_IPNETROW[] table = new MIB_IPNETROW[entries];
// Cycle through the entries.
for (int index = 0; index < entries; index++)
{
// Call PtrToStructure, getting the structure information.
table[index] = (MIB_IPNETROW) Marshal.PtrToStructure(new
IntPtr(currentBuffer.ToInt64() + (index *
Marshal.SizeOf(typeof(MIB_IPNETROW)))), typeof(MIB_IPNETROW));
}
for (int index = 0; index < entries; index++)
{
IPAddress ip=new IPAddress(table[index].dwAddr);
Console.Write("IP:"+ip.ToString()+"\t\tMAC:");
byte b;
b=table[index].mac0;
if ( b < 0x10)
{
Console.Write("0");
}
else
{
Console.Write("");
}
Console.Write(b.ToString("X"));
b=table[index].mac1;
if ( b < 0x10)
{
Console.Write("-0");
}
else
{
Console.Write("-");
}
Console.Write(b.ToString("X"));
b=table[index].mac2;
if ( b < 0x10)
{
Console.Write("-0");
}
else
{
Console.Write("-");
}
Console.Write(b.ToString("X"));
b=table[index].mac3;
if ( b < 0x10)
{
Console.Write("-0");
}
else
{
Console.Write("-");
}
Console.Write(b.ToString("X"));
b=table[index].mac4;
if ( b < 0x10)
{
Console.Write("-0");
}
else
{
Console.Write("-");
}
Console.Write(b.ToString("X"));
b=table[index].mac5;
if ( b < 0x10)
{
Console.Write("-0");
}
else
{
Console.Write("-");
}
Console.Write(b.ToString("X"));
Console.WriteLine();
}
}
finally
{
// Release the memory.
Marshal.FreeCoTaskMem(buffer);
}
}
}
}