c# - 为什么我的 ID 会随着互联网连接而改变？

Question

我正在关注 this tutorial为系统生成唯一的硬件 ID。问题是生成的 ID 在连接互联网时是不同的，而在互联网断开连接时是不同的。

这是我正在使用的代码:

    private static string fingerPrint = string.Empty;
    public static string GetUniqueID()
    {
        if (string.IsNullOrEmpty(fingerPrint))
        {
            fingerPrint = GetHash("CPU " + cpuId() + "\nBIOS " + 
                biosId() + "\nBASE " + baseId()
                + "\nVIDEO " + videoId() +"\nMAC "+ macId()
            );
        }
        return fingerPrint;
    }
    private static string GetHash(string s)
    {
        MD5 sec = new MD5CryptoServiceProvider();
        ASCIIEncoding enc = new ASCIIEncoding();
        byte[] bt = enc.GetBytes(s);
        return GetHexString(sec.ComputeHash(bt));
    }
    private static string GetHexString(byte[] bt)
    {
        string s = string.Empty;
        for (int i = 0; i < bt.Length; i++)
        {
            byte b = bt[i];
            int n, n1, n2;
            n = (int)b;
            n1 = n & 15;
            n2 = (n >> 4) & 15;
            if (n2 > 9)
                s += ((char)(n2 - 10 + (int)'A')).ToString();
            else
                s += n2.ToString();
            if (n1 > 9)
                s += ((char)(n1 - 10 + (int)'A')).ToString();
            else
                s += n1.ToString();
            if ((i + 1) != bt.Length && (i + 1) % 2 == 0) s += "-";
        }
        return s;
    }

    private static string identifier
    (string wmiClass, string wmiProperty, string wmiMustBeTrue)
    {
        string result = "";
        System.Management.ManagementClass mc = 
    new System.Management.ManagementClass(wmiClass);
        System.Management.ManagementObjectCollection moc = mc.GetInstances();
        foreach (System.Management.ManagementObject mo in moc)
        {
            if (mo[wmiMustBeTrue].ToString() == "True")
            {
                //Only get the first one
                if (result == "")
                {
                    try
                    {
                        result = mo[wmiProperty].ToString();
                        break;
                    }
                    catch
                    {
                    }
                }
            }
        }
        return result;
    }

    private static string identifier(string wmiClass, string wmiProperty)
    {
        string result = "";
        System.Management.ManagementClass mc = 
    new System.Management.ManagementClass(wmiClass);
        System.Management.ManagementObjectCollection moc = mc.GetInstances();
        foreach (System.Management.ManagementObject mo in moc)
        {
            if (result == "")
            {
                try
                {
                    result = mo[wmiProperty].ToString();
                    break;
                }
                catch
                {
                }
            }
        }
        return result;
    }
    private static string cpuId()
    {
        string retVal = identifier("Win32_Processor", "UniqueId");
        if (retVal == "")
        {
            retVal = identifier("Win32_Processor", "ProcessorId");
            if (retVal == "")
            {
                retVal = identifier("Win32_Processor", "Name");
                if (retVal == "") 
                {
                    retVal = identifier("Win32_Processor", "Manufacturer");
                }
                retVal += identifier("Win32_Processor", "MaxClockSpeed");
            }
        }
        return retVal;
    }

    private static string biosId()
    {
        return identifier("Win32_BIOS", "Manufacturer")
        + identifier("Win32_BIOS", "SMBIOSBIOSVersion")
        + identifier("Win32_BIOS", "IdentificationCode")
        + identifier("Win32_BIOS", "SerialNumber")
        + identifier("Win32_BIOS", "ReleaseDate")
        + identifier("Win32_BIOS", "Version");
    }

    private static string diskId()
    {
        return identifier("Win32_DiskDrive", "Model")
        + identifier("Win32_DiskDrive", "Manufacturer")
        + identifier("Win32_DiskDrive", "Signature")
        + identifier("Win32_DiskDrive", "TotalHeads");
    }

    private static string baseId()
    {
        return identifier("Win32_BaseBoard", "Model")
        + identifier("Win32_BaseBoard", "Manufacturer")
        + identifier("Win32_BaseBoard", "Name")
        + identifier("Win32_BaseBoard", "SerialNumber");
    }

    private static string videoId()
    {
        return identifier("Win32_VideoController", "DriverVersion")
        + identifier("Win32_VideoController", "Name");
    }

    private static string macId()
    {
        return identifier("Win32_NetworkAdapterConfiguration", 
            "MACAddress", "IPEnabled");
    }

GetUniqueID() 是散列各种 ID 的函数。为什么在有网络和没有网络的情况下生成的 ID 不同？

Answer 1

我认为这是因为当您断开连接时，您的网络接口(interface)被禁用，因此无法检索 MAC 地址。