C++ File I/O: CreateFile, ReadFile & WriteFile

In C++, you can use the functions CreateFile, ReadFile, and WriteFile to create, read, and write files.

1. Create a file:

HANDLE hFile = CreateFile(TEXT("example.txt"), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile == INVALID_HANDLE_VALUE) {
    // 文件创建失败
    // 处理错误
}

1. Write to file.

DWORD dwBytesWritten;
char data[] = "Hello, World!";
if (!WriteFile(hFile, data, sizeof(data), &dwBytesWritten, NULL)) {
    // 写入文件失败
    // 处理错误
}

1. Read the file.

DWORD dwBytesRead;
char buffer[100];
if (!ReadFile(hFile, buffer, sizeof(buffer), &dwBytesRead, NULL)) {
    // 读取文件失败
    // 处理错误
} else {
    // 输出读取的内容
    cout << buffer << endl;
}

You need to include the Windows.h header file to use these functions. Also, remember to close the file handle after using the file.

CloseHandle(hFile);