Clipboard helpers were added #15

Samples/Sample.SimpleWindow/Program.cs

@@ -1,8 +1,5 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
 using System.Text;
-using System.Threading.Tasks;
 using WinApi.Gdi32;
 using WinApi.User32;
 using WinApi.Windows;
@@ -16,6 +13,9 @@ static int Main(string[] args)
         {
             using (var win = Window.Create<AppWindow>("Hello"))
             {
+                User32Methods.AddClipboardFormatListener(win.Handle);
+                User32Helpers.TrySetClipboardData(Encoding.Unicode.GetBytes("WOWSER\0"), ClipboardFormat.CF_UNICODETEXT);
+
                 win.Show();
                 return new EventLoop().Run(win);
             }
@@ -62,6 +62,15 @@ protected override void OnMessage(ref WindowMessage msg)
                     msg.Result = new IntPtr(1);
                     return;
                 }
+                case WM.CLIPBOARDUPDATE:
+                {
+                    if (User32Helpers.TryGetClipboardUnicodeText(out var text))
+                        User32Helpers.MessageBox(text, "You've just copied something");
+                    else
+                        User32Helpers.MessageBox("This form can handle only the text-copy event");
+                    break;
+                }
+
             }
             base.OnMessage(ref msg);
         }

Samples/Sample.Win32/Program.cs

@@ -50,6 +50,8 @@ static int Main(string[] args)
             User32Methods.ShowWindow(hwnd, ShowWindowCommands.SW_SHOWNORMAL);
             User32Methods.UpdateWindow(hwnd);
 
+            User32Methods.AddClipboardFormatListener(hwnd);
+
             Message msg;
             int res;
             while ((res = User32Methods.GetMessage(out msg, IntPtr.Zero, 0, 0)) != 0)
@@ -83,6 +85,14 @@ private static IntPtr WindowProc(IntPtr hwnd, uint umsg,
                     User32Methods.EndPaint(hwnd, ref ps);
                     break;
                 }
+                case WM.CLIPBOARDUPDATE:
+                {
+                    if (User32Helpers.TryGetClipboardUnicodeText(out var text))
+                        User32Helpers.MessageBox(text, "You've just copied something");
+                    else
+                        User32Helpers.MessageBox("This form can handle only the text-copy event");
+                    break;
+                }
             }
             return User32Methods.DefWindowProc(hwnd, umsg, wParam, lParam);
         }

WinApi/User32/Helpers.cs

@@ -1,6 +1,13 @@
 using System;
+using System.Collections;
+using System.IO;
+using System.Linq;
 using System.Runtime.InteropServices;
+using System.Text;
+using NetCoreEx.BinaryExtensions;
 using NetCoreEx.Geometry;
+using WinApi.Gdi32;
+using WinApi.Kernel32;
 
 namespace WinApi.User32
 {
@@ -213,5 +220,107 @@ public static bool InverseAdjustWindowRectEx(
             if (res) Rectangle.Subtract(ref lpRect, ref rc);
             return res;
         }
+
+        #region Clipboard helpers
+
+        /// <summary>
+        /// Will try to set the specified data to the clipboard. 
+        /// If it is a string keep in mind that string should be passed with a null-terminated character.
+        /// </summary>
+        /// <param name="data">The data to set</param>
+        /// <param name="clipboardFormat"></param>
+        /// <returns></returns>
+        public static bool TrySetClipboardData(byte[] data, ClipboardFormat clipboardFormat)
+        {
+            if (!User32Methods.OpenClipboard(new IntPtr())) return false;
+
+            var bytesLength = data.Length;
+            var allocatedMemory = Marshal.AllocHGlobal(bytesLength);
+
+            Marshal.Copy(data, 0, allocatedMemory, bytesLength);
+
+            var result = User32Methods.SetClipboardData((uint)clipboardFormat, allocatedMemory);
+
+            //https://msdn.microsoft.com/en-us/library/windows/desktop/ms649051%28v=vs.85%29.aspx
+            // If SetClipboardData succeeds, the system owns the object identified by the hMem parameter.
+            // The application may not write to or free the data once ownership has been transferred to the system, 
+            //but it can lock and read from the data until the CloseClipboard function is called
+
+            //The allocated memory should not be freed
+
+            return User32Methods.CloseClipboard() && result != IntPtr.Zero;
+        }
+
+        /// <summary>
+        /// Will try to set the specified text to the clipboard
+        /// </summary>
+        /// <param name="textToSet">The text to set</param>
+        /// <returns></returns>
+        public static bool TrySetClipboardUnicodeText(string textToSet)
+        {
+            if (!User32Methods.OpenClipboard(new IntPtr())) return false;
+
+            var ptrToStr = Marshal.StringToHGlobalUni(textToSet);
+
+            var result = User32Methods.SetClipboardData((uint)ClipboardFormat.CF_UNICODETEXT, ptrToStr);
+
+            //https://msdn.microsoft.com/en-us/library/windows/desktop/ms649051%28v=vs.85%29.aspx
+            // If SetClipboardData succeeds, the system owns the object identified by the hMem parameter.
+            // The application may not write to or free the data once ownership has been transferred to the system, 
+            //but it can lock and read from the data until the CloseClipboard function is called
+
+            //The allocated memory should not be freed
+
+            return User32Methods.CloseClipboard() && result != IntPtr.Zero;
+        }
+
+        /// <summary>
+        /// Will try to get a unicode-string from the clipbard
+        /// </summary>
+        /// <param name="outString"></param>
+        /// <returns></returns>
+        public static unsafe bool TryGetClipboardUnicodeText(out string outString)
+        {
+            outString = string.Empty;
+            if (!User32Methods.OpenClipboard(new IntPtr())) return true;
+
+            var ptrToData = User32Methods.GetClipboardData((uint)ClipboardFormat.CF_UNICODETEXT);
+
+            if (User32Methods.CloseClipboard() == false || ptrToData == IntPtr.Zero)
+                return false;
+
+            outString = new string((char*)ptrToData);
+
+            return true;
+        }
+
+        /// <summary>
+        /// Will try to retrieve the first available clipboard format.
+        /// </summary>
+        /// <param name="format"></param>
+        /// <param name="clipBoardFormat"></param>
+        /// <returns></returns>
+        public static unsafe bool TryGetPriorityClipboardFormat(ClipboardFormat[] format, out ClipboardFormat clipBoardFormat)
+        {
+            clipBoardFormat = ClipboardFormat.CF_ZERO;
+            fixed (ClipboardFormat* first = &format[0])
+            {
+                var result = User32Methods.GetPriorityClipboardFormat((IntPtr)first, format.Length);
+
+                //https://msdn.microsoft.com/ru-ru/library/windows/desktop/ms649045(v=vs.85).aspx
+                switch (result)
+                {
+                    case -1:
+                        return false;
+                    case 0:
+                        return true;
+                    default:
+                        clipBoardFormat = (ClipboardFormat)result;
+                        return true;
+                }
+            }
+        }
+
+        #endregion
     }
 }