Windows API应用：CreateFile，WriteFile，ReadFile

CreateFile 跟 fopen 不同，打开文件时不区分 文本方式 或 二进制 方式

ReadFile 或 WriteFile 都是对二进制数据进行操作

HANDLE WINAPI CreateFile(
  __in          LPCTSTR lpFileName,             // 文件路径
  __in          DWORD dwDesiredAccess,          // 访问权限，GENERIC_READ | GENERIC_WRITE
  __in          DWORD dwShareMode,              // 共享模式，NULL | FILE_SHARE_READ | FILE_SHARE_WRITE
  __in          LPSECURITY_ATTRIBUTES lpSecurityAttributes,    // 安全属性
  __in          DWORD dwCreationDisposition,    // 创建配置，CREATE_ALWAYS | CREATE_NEW | OPEN_ALWAYS | OPEN_EXISTING
  __in          DWORD dwFlagsAndAttributes,     // 扩展属性，NULL | FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_READONLY
  __in          HANDLE hTemplateFile            // 指定一个文件句柄，新文件将从这个文件中复制扩展属性。NULL
);

BOOL WINAPI ReadFile(
  __in          HANDLE hFile,                   // 文件句柄
  __out         LPVOID lpBuffer,                // 接收数据用的 buffer
  __in          DWORD nNumberOfBytesToRead,     // 要读取的字节数
  __out         LPDWORD lpNumberOfBytesRead,    // 实际读取到的字节数
  __in          LPOVERLAPPED lpOverlapped       // OVERLAPPED 结构，一般设定为 NULL 
);

BOOL WINAPI WriteFile(
  __in          HANDLE hFile,                   // 文件句柄
  __in          LPCVOID lpBuffer,               // 要写入的数据
  __in          DWORD nNumberOfBytesToWrite,    // 要写入的字节数
  __out         LPDWORD lpNumberOfBytesWritten, // 实际写入的字节数
  __in          LPOVERLAPPED lpOverlapped       // OVERLAPPED 结构，一般设定为 NULL
);

DWORD WINAPI GetFileSize(
  __in          HANDLE hFile,                   // 文件句柄
  __out         LPDWORD lpFileSizeHigh          // high-order 的返回值，一般设定为 NULL
);

读文件：
void read(const wchar_t* strPath)
{
    HANDLE hFile = ::CreateFile(strPath, GENERIC_READ, 0, NULL, OPEN_EXISTING, NULL, NULL);
    if (hFile != INVALID_HANDLE_VALUE)
    {
        DWORD nFileSize = ::GetFileSize(hFile, NULL);
        char* lpBuffer = new char[nFileSize];
        DWORD nNumberOfBytesRead;
        BOOL bRet = ::ReadFile(hFile, lpBuffer, nFileSize, &nNumberOfBytesRead, NULL);
        
        // TODO ...
        
        delete[] lpBuffer;
        CloseHandle(hFile);
    }
}

写文件：
void write(const wchar_t* strPath, const wchar_t* strContent, const int nContentSize)
{
    HANDLE hFile = ::CreateFile(strPath, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, NULL, NULL);
    if (hFile != INVALID_HANDLE_VALUE)
    {
        DWORD nNumberOfBytesWritten;
        ::WriteFile(hFile, strContent, nContentSize, &nNumberOfBytesWritten, NULL);
        
        // TODO ...
        
        CloseHandle(hFile);
    }
}