using System;

using System.Management;

using System.Windows.Forms;

namespace WindowsFormsApp8

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            ManagementClass manager = new ManagementClass("Win32_NetworkAdapterConfiguration");

            foreach (ManagementObject obj in manager.GetInstances())

            {

                if ((bool)obj["IPEnabled"])

                {

                    string mac3 = obj["MacAddress"].ToString();

                }

            }

        }

    }

}