从文本文件中提取和修改特定行

有一个网络接口的文本文件：

auto eth0 bri0
iface eth0 inet static
    address 192.168.1.118/24
iface eth0.110 inet manual
    vlan-raw-device eth0
iface bri0 inet static
    address 192.168.110.1/24
    bridge_ports eth0.110
    bridge_stp on
    bridge_maxwait 10 ```

您需要从 eth0 获取地址并将其替换为另一个地址，例如 192.168.1.13。

我创建了一个获取所有接口和 ip 的类：

 public class IpChangeService
{
    private readonly string[] configFile;
    private List<string> interfaceName = new List<string>();
    private List<string> ipAddress = new List<string>();
    private string currentAdapter;

    public IpChangeService(string[] configFile, string currentAdapter)
    {
        this.configFile = configFile;
        this.currentAdapter = currentAdapter;
    }

    public (IList<string> iface, IList<string> ipAddress) GetCurrentInterfaces()
    {
        foreach (var line in configFile)
        {
            if (line.Contains("iface") && line.Contains("inet static"))
            {
                if (interfaceName != null)
                {
                    var str = line.Split(' ')[1] + " ";
                    var strWithoutSpaces = str.Replace(" ", "");
                    interfaceName.Add(strWithoutSpaces);
                }
            }

            if (interfaceName!=null && line.Contains("address"))
            {
                // see http://stackoverflow.com/questions/4890789/regex-for-an-ip-address
                ipAddress.Add(Regex.Match(line, @"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}").Value);
            }
        }

        return (interfaceName, ipAddress);
    }

    public int GetCurrentInterfaceIndex()
    {
        return interfaceName.IndexOf(currentAdapter);
    }

嗯，在主程序中我接收数据并尝试写下来，但是我觉得这样不正确，而且它不能正常工作（地址被歪斜插入）！而且我仍然不知道如何在没有通过索引硬编码的情况下正确选择 ip。

iface eth0 inet static
    address 192.168.1.118/24168.1.13/24

 private static void Main(string[] args)
    {
        var fileName = $"{AppDomain.CurrentDomain.BaseDirectory}interfaces";
        var inputLines = File.ReadAllLines(fileName, Encoding.Default);
        string interfaceName;
        string ipAddress;
        var ipChangeService = new IpChangeService(inputLines, "eth0");

        var currentIface = ipChangeService.GetCurrentInterfaces();
        var index = ipChangeService.GetCurrentInterfaceIndex();

        interfaceName = currentIface.iface[index];
        ipAddress = currentIface.ipAddress[0]; //FIXME: ХАРДКОД! 

        Console.WriteLine(interfaceName);

        var s2 = "192.168.1.113/24"; // ip на который заменяем строчку

        var configText = File.ReadAllText(fileName, Encoding.Default);

        configText = configText
            .Remove(configText.IndexOf(currentIface.ipAddress[0], StringComparison.Ordinal), ipAddress.Length)
            .Insert(configText.IndexOf(currentIface.ipAddress[0], StringComparison.Ordinal), s2);

        using (var file = new StreamWriter(fileName))
        {
            file.Write(configText);
        }
        Console.ReadKey();
    }

但最重要的是，目前尚不清楚如何从所有现有的（可能有几个）中准确地选择 ip 地址 eth0。然后替换这个特定的子字符串。