NativeMethods.cs

using System;

namespace MyNamespace {
    ///// APIの利用に必要な構造体・共用体の定義　ここから /////
    [StructLayout(LayoutKind.Sequential)]
    public struct Win32Point
    {
        public Int32 X;
        public Int32 Y;
    };

    [StructLayout(LayoutKind.Sequential)]
    public struct MOUSEINPUT
    {
        public int dx;
        public int dy;
        public int mouseData;
        public int dwFlags;
        public int time;
        public IntPtr dwExtraInfo;
    };

    [StructLayout(LayoutKind.Sequential)]
    public struct KEYBDINPUT
    {
        public short wVk;
        public short wScan;
        public int dwFlags;
        public int time;
        public IntPtr dwExtraInfo;
    };

    [StructLayout(LayoutKind.Sequential)]
    public struct HARDWAREINPUT
    {
        public int uMsg;
        public short wParamL;
        public short wParamH;
    };

    [StructLayout(LayoutKind.Explicit)]
    public struct INPUT_UNION
    {
        [FieldOffset(0)] public MOUSEINPUT mouse;
        [FieldOffset(0)] public KEYBDINPUT keyboard;
        [FieldOffset(0)] public HARDWAREINPUT hardware;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct INPUT
    {
        public int type;
        public INPUT_UNION ui;
    };
    ///// APIの利用に必要な構造体・共用体の定義　ここまで /////

    public static class NativeMethods {
        
        // 定数の定義
        
        public const int INPUT_MOUSE = 0;
        public const int INPUT_KEYBOARD = 1;
        public const int INPUT_HARDWARE = 2;

        public const int MOUSEEVENTF_MOVE = 0x1;
        public const int MOUSEEVENTF_ABSOLUTE = 0x8000;
        public const int MOUSEEVENTF_LEFTDOWN = 0x2;
        public const int MOUSEEVENTF_LEFTUP = 0x4;
        public const int MOUSEEVENTF_RIGHTDOWN = 0x8;
        public const int MOUSEEVENTF_RIGHTUP = 0x10;
        public const int MOUSEEVENTF_MIDDLEDOWN = 0x20;
        public const int MOUSEEVENTF_MIDDLEUP = 0x40;
        public const int MOUSEEVENTF_WHEEL = 0x800;
        public const int WHEEL_DELTA = 120;

        public const int KEYEVENTF_KEYDOWN = 0x0;
        public const int KEYEVENTF_KEYUP = 0x2;
        public const int KEYEVENTF_EXTENDEDKEY = 0x1;
        
        
        
        // APIの読み込み
        
        [DllImport ("user32.dll")]
        public static extern void SendInput (int nInputs, ref INPUT pInputs, int cbsize);
    }
}