如何获取操作系统版本

OSVERSIONINFO OSVersionInfo;
 OSVersionInfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
 GetVersionEx(&OSVersionInfo); 
 if (OSVersionInfo.dwPlatformId == VER_PLATFORM_WIN32_NT 
  && OSVersionInfo.dwMajorVersion == 5 
  && OSVersionInfo.dwMinorVersion == 0)
 {
  //AfxMessageBox("Windows 2000 OS!");
  cout << "Windows 2000 OS!" << endl;
 }
 else if(OSVersionInfo.dwPlatformId == VER_PLATFORM_WIN32_NT 
  && OSVersionInfo.dwMajorVersion == 5 
  && OSVersionInfo.dwMinorVersion == 1)
 {
  //AfxMessageBox("Windows XP OS !");
  cout << "Windows XP OS !" << endl;
 }
 else if(OSVersionInfo.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS 
  && OSVersionInfo.dwMajorVersion == 4 
  && OSVersionInfo.dwMinorVersion == 0)
 {
  //AfxMessageBox("Windows 98 OS!");
  cout << "Windows 98 OS!" << endl;
 }