add ClipboardHook

src/Shared/HandyControl_Shared/Tools/Hook/ClipboardHook.cs

@@ -0,0 +1,43 @@
+using System;
+using System.Windows;
+using System.Windows.Interop;
+using HandyControl.Tools.Interop;
+
+namespace HandyControl.Tools
+{
+    public class ClipboardHook
+    {
+        private static HwndSource HWndSource;
+
+        private static IntPtr HookId = IntPtr.Zero;
+
+        public static event Action ContentChanged;
+
+        public static void Start()
+        {
+            if (HookId != IntPtr.Zero)
+            {
+                Stop();
+            }
+
+            HookId = new WindowInteropHelper(new Window()).EnsureHandle();
+            HWndSource = HwndSource.FromHwnd(HookId);
+            if (HWndSource != null)
+            {
+                HWndSource.AddHook(WinProc);
+                NativeMethods.AddClipboardFormatListener(HookId);
+            }
+        }
+
+        public static void Stop() => NativeMethods.RemoveClipboardFormatListener(HookId);
+
+        private static IntPtr WinProc(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam, ref bool handled)
+        {
+            if (msg == NativeMethods.WM_CLIPBOARDUPDATE)
+            {
+                ContentChanged?.Invoke();
+            }
+            return IntPtr.Zero;
+        }
+    }
+}