FancyInput/FancyInput/Common/Utility.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace FancyInput.Common
{
    public class Utility
    {
        public static bool TrySetClipboardText(string text, out string errorDetail)
        {
            if (TrySetClipboardTextViaWin32(text, out var win32Error))
            {
                errorDetail = string.Empty;
                return true;
            }

            errorDetail = win32Error == 0 ? "Win32 未知错误" : $"Win32 0x{win32Error:X8}";
            return false;
        }

        private static bool TrySetClipboardTextViaWin32(string text, out int win32Error)
        {
            const int maxOpenRetries = 12;
            const int openRetryDelayMs = 10;
            const uint cfUnicodeText = 13;
            const uint gmemMoveable = 0x0002;
            const uint gmemZeroInit = 0x0040;

            win32Error = 0;
            var opened = false;
            var hGlobal = IntPtr.Zero;

            try
            {
                for (var i = 0; i < maxOpenRetries; i++)
                {
                    if (OpenClipboard(IntPtr.Zero))
                    {
                        opened = true;
                        break;
                    }

                    win32Error = Marshal.GetLastWin32Error();
                    Thread.Sleep(openRetryDelayMs);
                }

                if (!opened)
                {
                    return false;
                }

                if (!EmptyClipboard())
                {
                    win32Error = Marshal.GetLastWin32Error();
                    return false;
                }

                var bytes = Encoding.Unicode.GetBytes(text + '\0');
                hGlobal = GlobalAlloc(gmemMoveable | gmemZeroInit, (UIntPtr)bytes.Length);
                if (hGlobal == IntPtr.Zero)
                {
                    win32Error = Marshal.GetLastWin32Error();
                    return false;
                }

                var target = GlobalLock(hGlobal);
                if (target == IntPtr.Zero)
                {
                    win32Error = Marshal.GetLastWin32Error();
                    return false;
                }

                try
                {
                    Marshal.Copy(bytes, 0, target, bytes.Length);
                }
                finally
                {
                    GlobalUnlock(hGlobal);
                }

                if (SetClipboardData(cfUnicodeText, hGlobal) == IntPtr.Zero)
                {
                    win32Error = Marshal.GetLastWin32Error();
                    return false;
                }

                // Ownership has transferred to the clipboard.
                hGlobal = IntPtr.Zero;
                return true;
            }
            finally
            {
                if (opened)
                {
                    CloseClipboard();
                }

                if (hGlobal != IntPtr.Zero)
                {
                    GlobalFree(hGlobal);
                }
            }
        }

        [DllImport("user32.dll", SetLastError = true)]
        private static extern bool OpenClipboard(IntPtr hWndNewOwner);

        [DllImport("user32.dll", SetLastError = true)]
        private static extern bool CloseClipboard();

        [DllImport("user32.dll", SetLastError = true)]
        private static extern bool EmptyClipboard();

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr SetClipboardData(uint uFormat, IntPtr hMem);

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern IntPtr GlobalAlloc(uint uFlags, UIntPtr dwBytes);

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern IntPtr GlobalLock(IntPtr hMem);

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern bool GlobalUnlock(IntPtr hMem);

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern IntPtr GlobalFree(IntPtr hMem);
    }
}