C# 通过IP获取Mac地址（ARP）

C# 通过IP获取Mac地址

[DllImport("Iphlpapi.dll")]
private static unsafe extern int SendARP(Int32 dest, Int32 host, ref Int32 mac, ref Int32 length);

[DllImport("Ws2_32.dll")]
private static extern Int32 inet_addr(string ip);

public static string GetMACFromIP(string ip)
{
    string strRet = "";
    Int32 intDest = inet_addr(ip);
    Int32[] arrMAC = new Int32[2];
    Int32 intLen = 6;
    int intResult = SendARP(intDest, 0, ref arrMAC[0], ref intLen);
    if (intResult == 0)
    {
        Byte[] arrbyte = new Byte[8];
        arrbyte[5] = (Byte)(arrMAC[1] >> 8);
        arrbyte[4] = (Byte)arrMAC[1];
        arrbyte[3] = (Byte)(arrMAC[0] >> 24);
        arrbyte[2] = (Byte)(arrMAC[0] >> 16);
        arrbyte[1] = (Byte)(arrMAC[0] >> 8);
        arrbyte[0] = (Byte)arrMAC[0];
        StringBuilder strbMAC = new StringBuilder();
        for (int intIndex = 0; intIndex < 6; intIndex++)
        {
            if (intIndex > 0) strbMAC.Append("-");
            strbMAC.Append(arrbyte[intIndex].ToString("X2"));
        }
        strRet = strbMAC.ToString();
    }
    return strRet;
}