Detailed explanation of the code case for obtaining the local IP address (ipv4) in C#

 string name = Dns.GetHostName(); 
 IPAddress[] ipadrlist = Dns.GetHostAddresses(name);

string name = Dns.GetHostName(); 
IPAddress[] ipadrlist = Dns.GetHostAddresses(name); 
foreach (IPAddress ipa in ipadrlist) 
{ 
  if (ipa.AddressFamily == AddressFamily.InterNetwork) 
  Console.Writeline(ipa.ToString()); 
}

/// <summary> 
 /// 获取当前使用的IP 
 /// </summary> 
 /// <returns></returns> 
 public static string GetLocalIP() 
 { 
 string result = RunApp("route", "print",true); 
 Match m = Regex.Match(result, @"0.0.0.0\s+0.0.0.0\s+(\d+.\d+.\d+.\d+)\s+(\d+.\d+.\d+.\d+)"); 
 if (m.Success) 
 { 
  return m.Groups[2].Value; 
 } 
 else 
 { 
  try 
  { 
  System.Net.Sockets.TcpClient c = new System.Net.Sockets.TcpClient(); 
  c.Connect("www.baidu.com", 80); 
  string ip = ((System.Net.IPEndPoint)c.Client.LocalEndPoint).Address.ToString(); 
  c.Close(); 
  return ip; 
  } 
  catch (Exception) 
  { 
  return null; 
  } 
 } 
 } 
 /// <summary> 
 /// 获取本机主DNS 
 /// </summary> 
 /// <returns></returns> 
 public static string GetPrimaryDNS() 
 { 
 string result = RunApp("nslookup", "",true); 
 Match m = Regex.Match(result, @"\d+\.\d+\.\d+\.\d+"); 
 if (m.Success) 
 { 
  return m.Value; 
 } 
 else 
 { 
  return null; 
 } 
 } 
 /// <summary> 
 /// 运行一个控制台程序并返回其输出参数。 
 /// </summary> 
 /// <param name="filename">程序名</param> 
 /// <param name="arguments">输入参数</param> 
 /// <returns></returns> 
 public static string RunApp(string filename, string arguments,bool recordLog) 
 { 
 try 
 { 
  if (recordLog) 
  { 
  Trace.WriteLine(filename + " " + arguments); 
  } 
  Process proc = new Process(); 
  proc.StartInfo.FileName = filename; 
  proc.StartInfo.CreateNoWindow = true; 
  proc.StartInfo.Arguments = arguments; 
  proc.StartInfo.RedirectStandardOutput = true; 
  proc.StartInfo.UseShellExecute = false; 
  proc.Start(); 
  using (System.IO.StreamReader sr = new System.IO.StreamReader(proc.StandardOutput.BaseStream, Encoding.Default)) 
  { 
  //string txt = sr.ReadToEnd(); 
  //sr.Close(); 
  //if (recordLog) 
  //{ 
  // Trace.WriteLine(txt); 
  //} 
  //if (!proc.HasExited) 
  //{ 
  // proc.Kill(); 
  //} 
  //上面标记的是原文，下面是我自己调试错误后自行修改的 
  Thread.Sleep(100);  //貌似调用系统的nslookup还未返回数据或者数据未编码完成，程序就已经跳过直接执行 
      //txt = sr.ReadToEnd()了，导致返回的数据为空，故睡眠令硬件反应 
  if (!proc.HasExited)  //在无参数调用nslookup后，可以继续输入命令继续操作，如果进程未停止就直接执行 
  {    //txt = sr.ReadToEnd()程序就在等待输入，而且又无法输入，直接掐住无法继续运行 
   proc.Kill(); 
  } 
  string txt = sr.ReadToEnd(); 
  sr.Close(); 
  if (recordLog) 
   Trace.WriteLine(txt); 
  return txt; 
  } 
 } 
 catch (Exception ex) 
 { 
  Trace.WriteLine(ex); 
  return ex.Message; 
 } 
 }

private void GetIP() 
 { 
 Process cmd = new Process(); 
 cmd.StartInfo.FileName = "ipconfig.exe";//设置程序名 
 cmd.StartInfo.Arguments = "/all"; //参数 
 //重定向标准输出 
 cmd.StartInfo.RedirectStandardOutput = true; 
 cmd.StartInfo.RedirectStandardInput = true; 
 cmd.StartInfo.UseShellExecute = false; 
 cmd.StartInfo.CreateNoWindow = true;//不显示窗口（控制台程序是黑屏） 
 //cmd.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;//暂时不明白什么意思 
 /* 
 收集一下 有备无患 
 关于:ProcessWindowStyle.Hidden隐藏后如何再显示？ 
 hwndWin32Host = Win32Native.FindWindow(null, win32Exinfo.windowsName); 
 Win32Native.ShowWindow(hwndWin32Host, 1); //先FindWindow找到窗口后再ShowWindow 
 */ 
 cmd.Start(); 
 string info = cmd.StandardOutput.ReadToEnd(); 
 cmd.WaitForExit(); 
 cmd.Close(); 
 textBox1.AppendText(info); 
 }