C# 模擬鼠標、鍵盤事件、獲取控件相對屏幕位置

假設winform有一個按鈕和一個控件secondPic_1，現需求如下：

點擊按鈕實現鼠標自動移動到secondPic_1中央部位，點擊鼠標左鍵，並模擬鍵盤輸入‘M’。

#region 鼠標、鍵盤點擊
        [DllImport("user32.dll", EntryPoint = "keybd_event", SetLastError = true)]
        public static extern void keybd_event(Keys bVk, byte bScan, uint dwFlags, uint dwExtraInfo);
        const int KEYEVENTF_KEYUP = 0x0002;

        //模擬鼠標點擊
        [System.Runtime.InteropServices.DllImport("user32")]
        private static extern int mouse_event(int dwFlags, int dx, int dy, int cButtons, int dwExtraInfo);
        //模擬鍵盤點擊
        [DllImport("user32.dll", EntryPoint = "PostMessageA", SetLastError = true)]
        public static extern int PostMessage(IntPtr hWnd, int Msg, Keys wParam, int lParam);

        //移動鼠標 
        const int MOUSEEVENTF_MOVE = 0x0001;
        //模擬鼠標左鍵按下 
        const int MOUSEEVENTF_LEFTDOWN = 0x0002;
        //模擬鼠標左鍵擡起 
        const int MOUSEEVENTF_LEFTUP = 0x0004;
        //標示是否採用絕對座標 
        const int MOUSEEVENTF_ABSOLUTE = 0x8000;
        //模擬鼠標右鍵按下 
        const int MOUSEEVENTF_RIGHTDOWN = 0x0008;
        //模擬鼠標右鍵擡起 
        const int MOUSEEVENTF_RIGHTUP = 0x0010;
        #endregion

        /// <summary>
        /// 獲取控件相對於屏幕左上角的位置
        /// </summary>
        /// <param name="c"></param>
        /// <returns></returns>
        private Point LocationOnClient(Control c)
        {
            Point retval = new Point(0, 0);
            do
            {
                retval.Offset(c.Location);
                c = c.Parent;
            }
            while (c != null);
            return retval;
        }
       
        /// <summary>
        /// 點擊按鈕，鼠標自動移動到某個控件，左擊控件並鍵入鍵盤M鍵
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void pictureBox20_Click(object sender, EventArgs e)
        {
            //獲取電腦分辨率
            int sceenHeight = Screen.PrimaryScreen.Bounds.Height;
            int screenWeight = Screen.PrimaryScreen.Bounds.Width;

            //獲取控件的位置
            Point screen = LocationOnClient(secondPic_1);
            Point screenP = new Point(screen.X + secondPic_1.Size.Width / 2, screen.Y + secondPic_1.Size.Height / 2);
            Console.WriteLine("相對屏幕：" + screenP.X + "  " + screenP.Y);

            //將鼠標移動到控件的位置上，模擬鼠標左擊
            mouse_event(MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_MOVE | MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_LEFTUP, screenP.X * 65536 / screenWeight, screenP.Y * 65536 / sceenHeight, 0, 0);
           
            //模擬鍵盤輸入
            keybd_event(Keys.M, 0, 0, 0);
        }