NetworkInterface.GetIsNetworkAvailable()

------解决方案--------------------
ping一下不就好了

------解决方案--------------------
C# code

        private static ManagementClass mc;
        private static ManagementObjectCollection moc;
mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
                moc = mc.GetInstances();

                foreach (ManagementObject mo in moc) //查找网卡配置
                {
string s = ((string)mo["Caption"]);

                        if (s == NIC)
                        {
                            if ((bool)mo["DHCPEnabled"])  //此网卡未配置过IP
                            {
                                string[] ips = new string[1] { LocalIP };
                                string[] masks = new string[1] { StationIPmask };
                                Object[] objs = new object[2] { ips, masks };
                                mo.InvokeMethod("EnableStatic", objs);
                                NICValid = false;
                                return;
                            }

                            string[] str = (string[])mo["IPAddress"]; //多个ip地址

                            if (str.Length >= 3)
                            {
                                InfoString = "不能有多个IP地址绑定在此网卡上！";
                                NICValid = false;
                                return;
                            }

                            if (str.Length < 0)
                            {
                                InfoString = "请检查网卡设备！";
                                NICValid = false;
                                return;
                            }

                            if (str[0] == "0.0.0.0")
                            {
                                InfoString = "请检查网卡与交换机正确连接！";
                                NICValid = false;
                                return;
                            }
}