C# - P/Invoke 호출 예제

1. 시스템 상태를 얻어오거나 제어하는 함수

[DllImport("user32.dll", EntryPoint="SystemParametersInfoA")]

public static extern bool SystemParametersInfo ( int uiAction, int uiParam, [MarshalAs(UnmanagedType.Bool)] ref bool pvParam, int fWinIni );

public const int SPI_GETSCREENSAVEACTIVE = 0x10; // 16

public const int SPI_SETSCREENSAVEACTIVE = 0x11; // 17

public const int SPI_GETSCREENSAVERRUNNING = 0x72; // 97

public const int SPI_SETSCREENSAVERRUNNING = 0x61; // 114

public const int SPIF_UPDATEINIFILE = 0x0001;

public const int SPIF_SENDCHANGE = 0x0002;

2. 화면상태(해상도, 창 위치)를 제어하는 함수

[StructLayout(LayoutKind.Sequential)]

public struct DEVMODE 

{

[MarshalAs(UnmanagedType.ByValTStr,SizeConst=32)] public string dmDeviceName;

public short  dmSpecVersion;

public short  dmDriverVersion;

public short  dmSize;

public short  dmDriverExtra;

public int    dmFields;

public short dmOrientation;

public short dmPaperSize;

public short dmPaperLength;

public short dmPaperWidth;

public short dmScale;

public short dmCopies;

public short dmDefaultSource;

public short dmPrintQuality;

public short dmColor;

public short dmDuplex;

public short dmYResolution;

public short dmTTOption;

public short dmCollate;

[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string dmFormName;

public short dmLogPixels;

public short dmBitsPerPel;

public int   dmPelsWidth;

public int   dmPelsHeight;

public int   dmDisplayFlags;

public int   dmDisplayFrequency;

public int   dmICMMethod;

public int   dmICMIntent;

public int   dmMediaType;

public int   dmDitherType;

public int   dmReserved1;

public int   dmReserved2;

public int   dmPanningWidth;

public int   dmPanningHeight;

};

[DllImport("user32.dll")]

public static extern int EnumDisplaySettings (string deviceName, int modeNum, ref DEVMODE devMode );         

[DllImport("user32.dll")]

public static extern int ChangeDisplaySettings(ref DEVMODE devMode, int flags);

public const int ENUM_CURRENT_SETTINGS = -1;

public const int CDS_UPDATEREGISTRY = 0x01;

public const int CDS_TEST = 0x02;

public const int DISP_CHANGE_SUCCESSFUL = 0;

public const int DISP_CHANGE_RESTART = 1;

public const int DISP_CHANGE_FAILED = -1;

[DllImport("user32.dll")]

public static extern int SetWindowPos (System.IntPtr hwnd, int hWndInsertAfter, int x, int y, int cx, int cy, int wFlags);

public const int HWND_NOTOPMOST = -2;

public const int HWND_TOPMOST = -1;

public const int SWP_NOMOVE = 0x0002;

public const int SWP_NOSIZE = 0x0001;

3. OS의 버전을 구하는 함수

[StructLayout(LayoutKind.Sequential)]

public struct OSVERSIONINFO

{

public int dwOSVersionInfoSize;

public int dwMajorVersion;

public int dwMinorVersion;

public int dwBuildNumber;

public int dwPlatformId;

[MarshalAs(UnmanagedType.ByValTStr, SizeConst=128)]

public String szCSDVersion;

}

[DllImport("kernel32", EntryPoint="GetVersionExA")]

public static extern bool GetVersionEx ( ref OSVERSIONINFO lpVersionInformation );

public const byte VK_NUMLOCK = 0x90;

public const int KEYEVENTF_EXTENDEDKEY = 0x0001;

public const int KEYEVENTF_KEYUP = 0x0002;

public const int VER_PLATFORM_WIN32_NT = 2;

public const int VER_PLATFORM_WIN32_WINDOWS = 1;

4. 윈도우 핫키 등록 함수

[DllImport("user32.dll")]

public static extern bool RegisterHotKey(

IntPtr hWnd,         // window to receive hot-key notification

int id,            // identifier of hot key

uint fsModifiers,  // key-modifier flags

uint vk            // virtual-key code

);

[DllImport("user32.dll")]

public static extern bool UnregisterHotKey(

IntPtr hWnd,  // window associated with hot key

int id      // identifier of hot key

);

5. 키보드의 상태를 제어하는 함수

[DllImport("user32.dll")]

public static extern int GetKeyState ( int nVirtKey );

[DllImport("user32.dll")]

public static extern int GetKeyboardState ( byte[] keyBuffer );

[DllImport("user32.dll")]

public static extern int SetKeyboardState ( byte[] keyBuffer );

[DllImport("user32.dll")]

public static extern void keybd_event ( byte bVk, byte bScan, int dwFlags, int dwExtraInfo );