问如何识别隔离网络

EN

using System;
using System.Runtime;
using System.Runtime.InteropServices;

    public class InternetCS
    {
        //Creating the extern function...
        [DllImport("wininet.dll")]
        private extern static bool InternetGetConnectedState( out int Description, int ReservedValue );

        //Creating a function that uses the API function...
        public static bool IsConnectedToInternet( )
        {
            int Desc ;
            return InternetGetConnectedState( out Desc, 0 ) ;
        }
    }