App: Add SerialPortWatcher

2025-11-09 23:46:19 +01:00
parent 01f4480a08
commit e6367da286
4 changed files with 121 additions and 6 deletions
--- a/Elwig/Helpers/SerialPortWatcher.cs
+++ b/Elwig/Helpers/SerialPortWatcher.cs
@@ -0,0 +1,54 @@
+using System;
+using System.IO.Ports;
+using System.Linq;
+using System.Management;
+
+namespace Elwig.Helpers {
+    public sealed class SerialPortWatcher : IDisposable {
+
+        private readonly ManagementEventWatcher _deviceArrivalWatcher;
+        private readonly ManagementEventWatcher _deviceRemovalWatcher;
+
+        private string[] _knownPorts;
+
+        public event EventHandler<string>? SerialPortConnected;
+        public event EventHandler<string>? SerialPortDisconnected;
+
+        public SerialPortWatcher() {
+            _knownPorts = SerialPort.GetPortNames();
+            _deviceArrivalWatcher = new ManagementEventWatcher("SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 2");
+            _deviceArrivalWatcher.EventArrived += (s, e) => OnDeviceArrived();
+            _deviceRemovalWatcher = new ManagementEventWatcher("SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 3");
+            _deviceRemovalWatcher.EventArrived += (s, e) => OnDeviceRemoved();
+            _deviceArrivalWatcher.Start();
+            _deviceRemovalWatcher.Start();
+
+        }
+
+        private void OnDeviceArrived() {
+            string[] currentPorts = SerialPort.GetPortNames();
+            var newPorts = currentPorts.Except(_knownPorts).ToArray();
+            foreach (var port in newPorts)
+                SerialPortConnected?.Invoke(this, port);
+            _knownPorts = currentPorts;
+        }
+
+        private void OnDeviceRemoved() {
+            string[] currentPorts = SerialPort.GetPortNames();
+            var removedPorts = _knownPorts.Except(currentPorts).ToArray();
+            foreach (var port in removedPorts)
+                SerialPortDisconnected?.Invoke(this, port);
+            _knownPorts = currentPorts;
+        }
+
+        public void Dispose() {
+            try {
+                _deviceArrivalWatcher?.Stop();
+                _deviceRemovalWatcher?.Stop();
+            } finally {
+                _deviceArrivalWatcher?.Dispose();
+                _deviceRemovalWatcher?.Dispose();
+            }
+        }
+    }
+}