Filemapping和CreateFile函数实现以下功能：从1.txt中读数据，写到新文件2.txt中

好的，下面是一个简单的示例代码，实现从1.txt中读取数据，写到新文件2.txt中，使用Filemapping和CreateFile函数：

HANDLE hFile1 = CreateFile("1.txt", GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile1 == INVALID_HANDLE_VALUE)
{
    printf("Error opening file. Error code: %d\n", GetLastError());
    return;
}

DWORD dwFileSize = GetFileSize(hFile1, NULL);

HANDLE hMapFile = CreateFileMapping(hFile1, NULL, PAGE_READONLY, 0, 0, NULL);
if (hMapFile == NULL)
{
    printf("Error creating file mapping. Error code: %d\n", GetLastError());
    CloseHandle(hFile1);
    return;
}

LPVOID lpMapAddress = MapViewOfFile(hMapFile, FILE_MAP_READ, 0, 0, 0);
if (lpMapAddress == NULL)
{
    printf("Error mapping view of file. Error code: %d\n", GetLastError());
    CloseHandle(hMapFile);
    CloseHandle(hFile1);
    return;
}

HANDLE hFile2 = CreateFile("2.txt", GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile2 == INVALID_HANDLE_VALUE)
{
    printf("Error creating file. Error code: %d\n", GetLastError());
    UnmapViewOfFile(lpMapAddress);
    CloseHandle(hMapFile);
    CloseHandle(hFile1);
    return;
}

DWORD dwBytesWritten;
if (!WriteFile(hFile2, lpMapAddress, dwFileSize, &dwBytesWritten, NULL))
{
    printf("Error writing file. Error code: %d\n", GetLastError());
}

UnmapViewOfFile(lpMapAddress);
CloseHandle(hMapFile);
CloseHandle(hFile1);
CloseHandle(hFile2);

注意：此示例代码仅供参考，您需要根据自己的需求进行修改。