Windows のクリップボード実装に関するメモ書き

#include <windows.h>
#include <iostream>
#include <string>

void OpenClipboardWithSleep() {

    if (!OpenClipboard(NULL)) {
        std::cerr << "Failed to open clipboard." << std::endl;
        return;
    }

    // Sleep for demonstration purposes (not required in production)
    Sleep(10000);

    CloseClipboard();

}

int wmain() {

    OpenClipboardWithSleep();
    return 0;
}

void ReadAndDumpClipboard() {

    if (!OpenClipboard(NULL)) {
        std::cerr << "Failed to open clipboard." << std::endl;
        return;
    }

    std::cout << "=== Clipboard Content Dump ===" << std::endl;

    UINT format = 0;
    int count = 0;

	// Enumerate all clipboard formats
    while ((format = EnumClipboardFormats(format)) != 0) {
        count++;
        std::wstring formatName = GetFormatNameString(format);

        std::wcout << L"[" << count << L"] Format ID: " << std::dec << format
            << L" | Name: " << formatName << std::endl;

		// Get clipboard data handle
        HANDLE hData = GetClipboardData(format);
        if (hData == NULL) {
            std::cout << "    [Error] GetClipboardData returned NULL." << std::endl;
            continue;
        }

		// If we can lock the data, we assume it's a memory block
        void* pData = GlobalLock(hData);
        if (pData) {
            size_t size = GlobalSize(hData);
            std::cout << "    Type: Memory Block | Size: " << std::dec << size << " bytes" << std::endl << std::endl;

            PrintHexDump(pData, size);

            GlobalUnlock(hData);
        }
        else {
			// Fallback for non-lockable formats
            std::cout << "    Type: GDI Handle or Non-Lockable Object (Cannot dump raw bytes safely)" << std::endl << std::endl;
        }
    }

    if (count == 0) {
        std::cout << "Clipboard is empty." << std::endl;
    }

    CloseClipboard();

}

HANDLE GetClipboardData(
  [in] UINT uFormat
);

// Enumerate all clipboard formats
while ((format = EnumClipboardFormats(format)) != 0) { }

// If we can lock the data, we assume it's a memory block
void* pData = GlobalLock(hData);
if (pData) {
    size_t size = GlobalSize(hData);
    std::cout << "    Type: Memory Block | Size: " << std::dec << size << " bytes" << std::endl << std::endl;

    PrintHexDump(pData, size);

    GlobalUnlock(hData);
}

// Using Win32 API to write and read clipboard text
bool WriteTextToClipboard(const std::wstring& text) {
    
    if (!OpenClipboard(NULL)) {
        std::cerr << "Failed to open clipboard." << std::endl;
        return false;
    }
    if (!EmptyClipboard()) {
        std::cerr << "Failed to empty clipboard." << std::endl;
        CloseClipboard();
        return false;
	}

	// Calculate size in bytes (including null terminator)
    size_t size = (text.length() + 1) * sizeof(wchar_t);

	// Need to allocate global memory for clipboard data(GMEM_MOVEABLE)
    HGLOBAL hGlob = GlobalAlloc(GMEM_MOVEABLE, size);
    if (!hGlob) {
        CloseClipboard();
        return false;
    }

	// Lock the memory and copy the text
    void* pMem = GlobalLock(hGlob);
    if (pMem) {

        memcpy(pMem, text.c_str(), size);
        GlobalUnlock(hGlob);

		// Set the clipboard data as CF_UNICODETEXT
        if (SetClipboardData(CF_UNICODETEXT, hGlob) == NULL) {
            GlobalFree(hGlob);
            std::cerr << "Failed to set clipboard data." << std::endl;
        }
        else {
            std::cout << "[Write] Successfully copied text to clipboard." << std::endl;
        }
    }

    CloseClipboard();
    return true;
}