/// <summary>
/// 获取网卡ID
/// </summary>
/// <returns></returns>
private static string GetMacAddressNum()
{
    try
    {
        string macStr = "";
        ManagementClass manc = new ManagementClass("Win32_NetworkAdapterConfiguration");
        ManagementObjectCollection manoc = manc.GetInstances();
        foreach (ManagementObject item in manoc)
            if ((bool)item["IPEnabled"] == true)
            {
                macStr += item["MacAddress"].ToString() + " ";
                break;
            }
        manoc = null;
        manc = null;
        return macStr.Trim();
    }
    catch (Exception e)
    {
        return e.Message;
    }
}