C# Signature:

[DllImport("user32.dll")]
static extern uint SendInput(uint nInputs, INPUT [] pInputs, int cbSize);

User-Defined Types:

INPUT

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

class Test
{
    public enum VK : ushort
    {
    SHIFT        = 0x10,
    CONTROL          = 0x11,
    MENU         = 0x12,
    ESCAPE           = 0x1B,
    BACK         = 0x08,
    TAB          = 0x09,
    RETURN           = 0x0D,
    PRIOR        = 0x21,
    NEXT         = 0x22,
    END          = 0x23,
    HOME         = 0x24,
    LEFT         = 0x25,
    UP           = 0x26,
    RIGHT        = 0x27,
    DOWN         = 0x28,
    SELECT           = 0x29,
    PRINT        = 0x2A,
    EXECUTE          = 0x2B,
    SNAPSHOT         = 0x2C,
    INSERT           = 0x2D,
    DELETE           = 0x2E,
    HELP         = 0x2F,
    NUMPAD0          = 0x60,
    NUMPAD1          = 0x61,
    NUMPAD2          = 0x62,
    NUMPAD3          = 0x63,
    NUMPAD4          = 0x64,
    NUMPAD5          = 0x65,
    NUMPAD6          = 0x66,
    NUMPAD7          = 0x67,
    NUMPAD8          = 0x68,
    NUMPAD9          = 0x69,
    MULTIPLY         = 0x6A,
    ADD          = 0x6B,
    SEPARATOR        = 0x6C,
    SUBTRACT         = 0x6D,
    DECIMAL          = 0x6E,
    DIVIDE           = 0x6F,
    F1           = 0x70,
    F2           = 0x71,
    F3           = 0x72,
    F4           = 0x73,
    F5           = 0x74,
    F6           = 0x75,
    F7           = 0x76,
    F8           = 0x77,
    F9           = 0x78,
    F10          = 0x79,
    F11          = 0x7A,
    F12          = 0x7B,
    OEM_1        = 0xBA,   // ',:' for US
    OEM_PLUS         = 0xBB,   // '+' any country
    OEM_COMMA        = 0xBC,   // ',' any country
    OEM_MINUS        = 0xBD,   // '-' any country
    OEM_PERIOD       = 0xBE,   // '.' any country
    OEM_2        = 0xBF,   // '/?' for US
    OEM_3        = 0xC0,   // '`~' for US
    MEDIA_NEXT_TRACK     = 0xB0,
    MEDIA_PREV_TRACK     = 0xB1,
    MEDIA_STOP           = 0xB2,
    MEDIA_PLAY_PAUSE     = 0xB3,
    LWIN       =0x5B,
    RWIN       =0x5C
    }

    public struct KEYBDINPUT
    {
    public WORD wVk;
    public WORD wScan;
    public DWORD dwFlags;
    public LONG time;
    public DWORD dwExtraInfo;
    };
    [StructLayout(LayoutKind.Explicit,Size=28)]
    public struct INPUT
    {
    [FieldOffset(0)] public DWORD type;
    [FieldOffset(4)] public KEYBDINPUT ki;
    };

    void Test()
    {
    INPUT structInput;
    structInput = new INPUT();
    structInput.type = Win32Consts.INPUT_KEYBOARD;

    // Key down shift, ctrl, and/or alt
    structInput.ki.wScan = 0;
    structInput.ki.time = 0;
    structInput.ki.dwFlags = 0;
    structInput.ki.dwExtraInfo = Win32.GetMessageExtraInfo();
    if (Shift)
    {
        structInput.ki.wVk = (ushort)VK.SHIFT;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Ctrl)
    {
        structInput.ki.wVk = (ushort)VK.CONTROL;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Alt)
    {
        structInput.ki.wVk = (ushort)VK.MENU;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Win)
    {
        structInput.ki.wVk = (ushort)VK.LWIN;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    // Key down the actual key-code
    structInput.ki.wVk = vk;
    intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    // Key up the actual key-code
    structInput.ki.dwFlags = Win32Consts.KEYEVENTF_KEYUP;
    intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    // Key up shift, ctrl, and/or alt
    if (Shift)
    {
        structInput.ki.wVk = (ushort)VK.SHIFT;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Ctrl)
    {
        structInput.ki.wVk = (ushort)VK.CONTROL;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Alt)
    {
        structInput.ki.wVk = (ushort)VK.MENU;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    if (Win)
    {
        structInput.ki.wVk = (ushort)VK.LWIN;
        intReturn = Win32.SendInput(1, ref structInput, (UInt32)sizeof(INPUT));
    }
    }
}

Alternative Managed API:

Do you know one? Please contribute it!