得到MAC地址

 /// <summary>
    /// 得到MAC地址
    /// </summary>
    /// <returns></returns>
    public string GetMacAddress()
    {
        ManagementClass mc;
        ManagementObjectCollection moc;
        try
        {
            mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
            moc = mc.GetInstances();
        }
        catch
        {
            return "";
        }
        //****先得到网卡数目                      
        int i = 0;
        foreach (ManagementObject mo in moc)
        {
            if ((bool)mo["IPEnabled"] == true)
            {
                i++;
            }
            mo.Dispose();
        }
        //***赋值给数组    
        ManagementClass mc_2 = new ManagementClass("Win32_NetworkAdapterConfiguration");
        ManagementObjectCollection moc_2 = mc_2.GetInstances();
        string[] array = new string[i];
        int j = 0;
        foreach (ManagementObject mo in moc_2)
        {
            if ((bool)mo["IPEnabled"] == true)
            {
                string temp = mo["MacAddress"].ToString();
                temp = temp.Replace(":", "-");
                array[j] = temp;
                j++;
            }
            mo.Dispose();

        }
        string retv = "";
        foreach (string s in array)
            retv += s;
        if (retv.Length > 17)
        {
            retv = retv.Substring(0, 17);
        }
        return retv;
    }