add ColorDropper

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

@@ -1,7 +1,48 @@
-namespace HandyControl.Tools
-{
-    public class MouseHook
-    {
+using System;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+using HandyControl.Data;
+using HandyControl.Tools.Interop;
 
+namespace HandyControl.Tools
+{
+    internal class MouseHook
+    {
+        public static event EventHandler<MouseHookEventArgs> StatusChanged;
+
+        private static IntPtr HookId = IntPtr.Zero;
+
+        private static readonly UnsafeNativeMethods.HookProc Proc = HookCallback;
+
+        public static void Start() => HookId = SetHook(Proc);
+
+        public static void Stop() => UnsafeNativeMethods.UnhookWindowsHookEx(HookId);
+
+        private static IntPtr SetHook(UnsafeNativeMethods.HookProc proc)
+        {
+            using (var curProcess = Process.GetCurrentProcess())
+            using (var curModule = curProcess.MainModule)
+            {
+                if (curModule != null)
+                {
+                    return UnsafeNativeMethods.SetWindowsHookEx((int) UnsafeNativeMethods.HookType.WH_MOUSE_LL, proc,
+                        UnsafeNativeMethods.GetModuleHandle(curModule.ModuleName), 0);
+                }
+                return IntPtr.Zero;
+            }
+        }
+
+        private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
+        {
+            if (nCode < 0) return UnsafeNativeMethods.CallNextHookEx(HookId, nCode, wParam, lParam);
+            var hookStruct = (UnsafeNativeMethods.MOUSEHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(UnsafeNativeMethods.MOUSEHOOKSTRUCT));
+            StatusChanged?.Invoke(null, new MouseHookEventArgs
+            {
+                Message = (MouseHookMessageType)wParam,
+                Point = new NativeMethods.POINT(hookStruct.pt.X, hookStruct.pt.Y)
+            });
+
+            return UnsafeNativeMethods.CallNextHookEx(HookId, nCode, wParam, lParam);
+        }
     }
 }

src/Shared/HandyControl_Shared/Tools/Interop/UnsafeNativeMethods.cs

@@ -174,5 +174,45 @@ namespace HandyControl.Tools.Interop
 
         [DllImport(ExternDll.User32, ExactSpelling = true, CharSet = CharSet.Auto)]
         public static extern bool SetForegroundWindow(IntPtr hWnd);
+
+        [DllImport(ExternDll.User32, CharSet = CharSet.Auto, SetLastError = true)]
+        public static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
+
+        [DllImport(ExternDll.Kernel32, CharSet = CharSet.Auto, SetLastError = true)]
+        public static extern IntPtr GetModuleHandle(string lpModuleName);
+
+        [DllImport(ExternDll.User32, CharSet = CharSet.Auto, SetLastError = true)]
+        public static extern bool UnhookWindowsHookEx(IntPtr hhk);
+
+        public enum HookType
+        {
+            WH_MOUSE_LL = 14,
+        }
+
+        [StructLayout(LayoutKind.Sequential)]
+        public struct MOUSEHOOKSTRUCT
+        {
+            public NativeMethods.POINT pt;
+            public IntPtr hwnd;
+            public uint wHitTestCode;
+            public IntPtr dwExtraInfo;
+        }
+
+        public delegate IntPtr HookProc(int code, IntPtr wParam, IntPtr lParam);
+
+        [DllImport(ExternDll.User32, CharSet = CharSet.Auto, SetLastError = true)]
+        public static extern IntPtr SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hMod, uint dwThreadId);
+
+        [DllImport(ExternDll.User32, SetLastError = true)]
+        public static extern IntPtr GetDesktopWindow();
+
+        [DllImport(ExternDll.User32, SetLastError = true)]
+        public static extern IntPtr GetWindowDC(IntPtr window);
+
+        [DllImport(ExternDll.Gdi32, SetLastError = true)]
+        public static extern uint GetPixel(IntPtr dc, int x, int y);
+
+        [DllImport(ExternDll.User32, SetLastError = true)]
+        public static extern int ReleaseDC(IntPtr window, IntPtr dc);
     }
 }