整理分享C#通过user32.dll模拟物理按键操作的代码

转载自：http://blog.skydev.cc/

对系统模拟按键方面的知识和按键映射代码做了一下梳理，在这里分享出来，适用于开发自动操作工具和游戏外挂。

主代码：

public const int KEYEVENTF_EXTENDEDKEY = 0x0001; //Key click flag
        public const int KEYEVENTF_KEYUP = 0x0002; //Key up flag
        [DllImport("user32.dll")]
        private static extern void keybd_event(byte bVk, byte bSCan, int dwFlags, int dwExtraInfo);
        [DllImport("user32.dll")]
        private static extern byte MapVirtualKey(byte wCode, int wMap);

        public static void 模拟按下按键(VirtualKeyCode 虚拟按键代码)
        {
            var code = (byte)虚拟按键代码;
            keybd_event(code, 0, 0, 0);
        }

        public static void 模拟弹起按键(VirtualKeyCode 虚拟按键代码)
        {
            var code = (byte) 虚拟按键代码;
            keybd_event(code, 0, KEYEVENTF_KEYUP, 0);
        }

        public static void 模拟单击按键(VirtualKeyCode 虚拟按键代码)
        {
            var code = (byte)虚拟按键代码;
            keybd_event(code, 0, KEYEVENTF_EXTENDEDKEY, 0);
        }

网上关于keybd_event的dwFlags参数功能说法很混乱，经我测试貌似是KEYEVENTF_EXTENDEDKEY表示一次单击，0表示按下，KEYEVENTF_KEYUP表示弹起，不一定完全正确，希望高人指点一下。

另外MapVirtualKey的作用实在不懂，所以就没用上，看到有人这么调用不知有什么区别：

var code = (byte)虚拟按键代码;
            keybd_event(code, MapVirtualKey(code,0), 0, 0);

我试过好像也没什么变化~到底MapVirtualKey是干什么用的呢？？

VirtualKeyCode枚举：

/// <summary>
    /// 虚拟按键代码
    /// 参考于 http://msdn.microsoft.com/zh-cn/library/dd375731(v=vs.85).aspx
    /// </summary>
    public enum VirtualKeyCode
    {
        /// <summary>
        /// Left mouse button
        /// </summary>
        Left_mouse_button = 0x01,
        /// <summary>
        /// Right mouse button
        /// </summary>
        Right_mouse_button = 0x02,
        /// <summary>
        /// Control-break processing
        /// </summary>
        Control_break_processing = 0x03,
        /// <summary>
        /// Middle mouse button (three-button mouse)
        /// </summary>
        Middle_mouse_button = 0x04,
        /// <summary>
        /// X1 mouse button
        /// </summary>
        X1_mouse_button = 0x05,
        /// <summary>
        /// X2 mouse button
        /// </summary>
        X2_mouse_button = 0x06,
        /// <summary>
        /// Undefined
        /// </summary>
        Undefined1 = 0x07,
        /// <summary>
        /// BACKSPACE key
        /// </summary>
        BACKSPACE_key = 0x08,
        /// <summary>
        /// TAB key
        /// </summary>
        TAB_key = 0x09,
        /// <summary>
        /// CLEAR key
        /// </summary>
        CLEAR_key = 0x0C,
        /// <summary>
        /// ENTER key
        /// </summary>
        ENTER_key = 0x0D,
        /// <summary>
        /// SHIFT key
        /// </summary>
        SHIFT_key = 0x10,
        /// <summary>
        /// CTRL key
        /// </summary>
        CTRL_key = 0x11,
        /// <summary>
        /// ALT key
        /// </summary>
        ALT_key = 0x12,
        /// <summary>
        /// PAUSE key
        /// </summary>
        PAUSE_key = 0x13,
        /// <summary>
        /// CAPS LOCK key
        /// </summary>
        CAPS_LOCK_key = 0x14,
        /// <summary>
        /// IME Kana mode
        /// </summary>
        IME_Kana_mode = 0x15,
        /// <summary>
        /// IME Hanguel mode (maintained for compatibility; use VK_HANGUL)
        /// </summary>
        IME_Hanguel_mode = 0x15,
        /// <summary>
        /// IME Hangul mode
        /// </summary>
        IME_Hangul_mode = 0x15,
        /// <summary>
        /// Undefined
        /// <