I present, with little introduction, the MACAddress class. Within you will find simple test and conversion methods, with a single, simple to use method for sending a WOL ‘Magic’ Packet.
// MACAddress Class (Sending WOL 'Magic' Packets)
// Written by John Storer II (Feb 20, 2012)
//
// Feel free to use/modify this code as you wish, without liability.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;
using System.Net;
namespace SendWOLPacket
{
public class MACAddress
{
/// <summary>
/// Test a MACAddress byte Array.
/// </summary>
/// <param name="macAddress"></param>
/// <returns></returns>
public static bool Test(byte[] macAddress) {
if (macAddress == null) return false;
if (macAddress.Length != 6) return false;
return true;
}
/// <summary>
/// Test a MACAddress string.
/// </summary>
/// <param name="macAddress"></param>
/// <returns></returns>
public static bool Test(string macAddress) {
var valid_chars = "0123456789ABCDEFabcdef";
if (string.IsNullOrEmpty(macAddress)) return false;
if (macAddress.Length != 12) return false;
foreach (var c in macAddress) {
if (valid_chars.IndexOf(c) < 0) {
return false;
}
}
return true;
}
/// <summary>
/// Parse a MACAddress string into a byte array.
/// </summary>
/// <param name="macAddress"></param>
/// <returns></returns>
public static byte[] Parse(string macAddress) {
byte[] mac = new byte[6];
if (!Test(macAddress))
throw new ArgumentException(
"Invalid MACAddress string.",
"macAddress",
null);
for (var i = 0; i < 6; i++) {
var t = macAddress.Substring((i * 2), 2);
mac[i] = Convert.ToByte(t, 16);
}
return mac;
}
/// <summary>
/// Attempt to parse a MACAddress string
/// without throwing an Exception.
/// </summary>
/// <param name="macAddress"></param>
/// <param name="Address"></param>
/// <returns></returns>
public static bool TryParse(string macAddress, out byte[] Address) {
try {
Address = Parse(macAddress);
return true;
}
catch {
Address = null;
return false;
}
}
/// <summary>
/// Convert a byte array MACAddress to a string.
/// </summary>
/// <param name="macAddress"></param>
/// <returns></returns>
public static string ToString(byte[] macAddress) {
if (!Test(macAddress))
throw new ArgumentException(
"Invalid MACAddress byte array.",
"macAddress",
null);
return BitConverter.ToString(macAddress).Replace("-", "");
}
/// <summary>
/// Sends a Wake-On-LAN 'magic' packet to
/// the specified MACAddress string.
/// </summary>
/// <param name="macAddress"></param>
public static void SendWOLPacket(string macAddress) {
if (!Test(macAddress))
throw new ArgumentException(
"Invalid MACAddress string.",
"macAddress",
null);
byte[] mac = Parse(macAddress);
SendWOLPacket(mac);
}
/// <summary>
/// Sends a Wake-On-LAN 'magic' packet to
/// the specified MACAddress byte array.
/// </summary>
/// <param name="macAddress"></param>
public static void SendWOLPacket(byte[] macAddress) {
if (!Test(macAddress))
throw new ArgumentException(
"Invalid MACAddress byte array.",
"macAddress",
null);
// WOL 'magic' packet is sent over UDP.
using (UdpClient client = new UdpClient()) {
// Send to: 255.255.255.0:40000 over UDP.
client.Connect(IPAddress.Broadcast, 40000);
// Two parts to a 'magic' packet:
// First is 0xFFFFFFFFFFFF,
// Second is 16 * MACAddress.
byte[] packet = new byte[17 * 6];
// Set to: 0xFFFFFFFFFFFF.
for (int i = 0; i < 6; i++) {
packet[i] = 0xFF;
}
// Set to: 16 * MACAddress
for (int i = 1; i <= 16; i++) {
for (int j = 0; j < 6; j++) {
packet[i * 6 + j] = macAddress[j];
}
}
// Send WOL 'magic' packet.
client.Send(packet, packet.Length);
}
}
}
}
Using this code is as simple as (assuming you have a form, a button named bSend and a text box named tbMACAddress):
private void bSend_Click(object sender, EventArgs e) {
try {
MACAddress.SendWOLPacket(tbMACAddress.Text);
MessageBox.Show(
string.Format("Packet Sent to '{0}'", tbMACAddress.Text));
}
catch (Exception Error) {
MessageBox.Show(
string.Format("Error:\n\n{0}", Error.Message), "Error");
}
}
Why write a class to send WOL Packets? Mainly because I needed to wake up a PC at home remotely, if I really needed it. Also, someone here at work said, “I need to send WOL to this laptop, but I don’t have the Altiris Console handy,” to which I replied:
Because who doesn't like a good challenge?
