C# 读取网络上下行（不要使用性能计数器的方式）

NetworkInterface networkInterface = NetworkInterface.GetAllNetworkInterfaces()             .FirstOrDefault(i => i.Name.Equals(interfaceName, StringComparison.OrdinalIgnoreCase));          if (networkInterface == null)         {             Console.WriteLine("Network interface not found.");             return;         }          PerformanceCounter downloadCounter = new PerformanceCounter("Network Interface", "Bytes Received/sec", networkInterface.Description);         PerformanceCounter uploadCounter = new PerformanceCounter("Network Interface", "Bytes Sent/sec", networkInterface.Description);          while (true)         {             float downloadSpeed = downloadCounter.NextValue();             float uploadSpeed = uploadCounter.NextValue();              Console.WriteLine($"Download Speed: {downloadSpeed} bytes/sec");             Console.WriteLine($"Upload Speed: {uploadSpeed} bytes/sec");              Thread.Sleep(1000); // 每秒更新一次网速         }

异常: System.InvalidOperationException: 类别不存在。    在 System.Diagnostics.PerformanceCounterLib.CounterExists(String machine, String category, String counter)    在 System.Diagnostics.PerformanceCounter.InitializeImpl()    在 System.Diagnostics.PerformanceCounter..ctor(String categoryName, String counterName, String instanceName, Boolean readOnly)    在 System.Diagnostics.PerformanceCounter..ctor(String categoryName, String counterName, String instanceName)

 string interfaceName = "Ethernet"; // 指定网络接口的名称          ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT * FROM Win32_PerfFormattedData_Tcpip_NetworkInterface");         ManagementObjectCollection objects = searcher.Get();          foreach (ManagementObject obj in objects)         {             string name = obj["Name"].ToString();              if (name.Equals(interfaceName, StringComparison.OrdinalIgnoreCase))             {                 ulong bytesReceived = Convert.ToUInt64(obj["BytesReceivedPerSec"]);                 ulong bytesSent = Convert.ToUInt64(obj["BytesSentPerSec"]);                  Console.WriteLine($"Download Speed: {bytesReceived} bytes/sec");                 Console.WriteLine($"Upload Speed: {bytesSent} bytes/sec");                  break;             }         }