GeekDesk/Util/ShowWindowFollowMouse.cs

using GeekDesk.Constant;
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Forms;

namespace GeekDesk.Util
{
    public class ShowWindowFollowMouse
    {

        public enum MousePosition
        {
            CENTER = 1,
            LEFT_TOP = 2,
            LEFT_BOTTOM = 3,
            RIGHT_TOP = 4,
            RIGHT_BOTTOM = 5,
            LEFT_CENTER = 6,
            RIGHT_CENTER = 7
        }

        public static void FollowMouse(Window window)
        {
            // Get the mouse position
            var mousePosition = System.Windows.Forms.Control.MousePosition;

            // Get the window size
            var windowWidth = window.Width;
            var windowHeight = window.Height;

            Console.WriteLine("windowWidth +  windowHeight:" + windowWidth + "+" +  windowHeight);

            // Get the screen where the mouse is located
            var screen = System.Windows.Forms.Screen.FromPoint(new System.Drawing.Point(mousePosition.X, mousePosition.Y));
            var workingArea = screen.WorkingArea;

            // Get the DPI scaling factor for the screen
            //float dpiX, dpiY;
            //using (var graphics = System.Drawing.Graphics.FromHwnd(IntPtr.Zero))
            //{
            //    dpiX = graphics.DpiX / 96f; // 96 is the default DPI
            //    dpiY = graphics.DpiY / 96f; // 96 is the default DPI
            //}

            float dpiX = GetDpi( true);
            float dpiY = GetDpi(false);

            // Convert mouse position to logical pixels based on DPI
            double mouseX = mousePosition.X / dpiX;
            double mouseY = mousePosition.Y / dpiY;

            // Calculate target position to center the window on the mouse
            double targetLeft = mouseX - windowWidth / 2;
            double targetTop = mouseY - windowHeight / 2;

            // Ensure the window does not exceed the screen boundaries
            if (targetLeft < workingArea.Left / dpiX)
                targetLeft = workingArea.Left / dpiX;
            if (targetLeft + windowWidth / dpiX > workingArea.Right / dpiX)
                targetLeft = workingArea.Right / dpiX - windowWidth / dpiX;

            if (targetTop < workingArea.Top / dpiY)
                targetTop = workingArea.Top / dpiY;
            if (targetTop + windowHeight / dpiY > workingArea.Bottom / dpiY)
                targetTop = workingArea.Bottom / dpiY - windowHeight / dpiY;

            // Update window position
            window.Left = targetLeft * dpiX;
            window.Top = targetTop * dpiY;
        }

        private static float GetDpi(bool isX)
        {
            IntPtr hdc = WindowUtil.GetDC(IntPtr.Zero);
            int dpi = isX ? WindowUtil.GetDeviceCaps(hdc, LOGPIXELSX) : WindowUtil.GetDeviceCaps(hdc, LOGPIXELSY);
            WindowUtil.ReleaseDC(IntPtr.Zero, hdc);
            return dpi / 96f;
        }

        private static IntPtr GetScreenHandleFromMouse()
        {
            // Get the mouse position
            var mousePosition = System.Windows.Forms.Control.MousePosition;

            // Convert mouse position to a POINT structure
            System.Drawing.Point point = new System.Drawing.Point(mousePosition.X, mousePosition.Y);

            // Get the window handle from the point
            IntPtr windowHandle = WindowUtil.WindowFromPoint(point);

            return windowHandle;
        }

        // Constants for DPI
        private const int HORZRES = 8;
        private const int VERTRES = 10;
        private const int LOGPIXELSX = 88;
        private const int LOGPIXELSY = 90;

       

        /// <summary>
        /// 随鼠标位置显示面板 
        /// </summary>
        public static void Show(Window window, MousePosition position, double widthOffset = 0, double heightOffset = 0)
        {
            //获取鼠标位置
            System.Windows.Point p = MouseUtil.GetMousePosition();

            float dpiX = GetDpi(true);
            float dpiY = GetDpi(false);
            p.X = p.X / dpiX;
            p.Y = p.Y / dpiY;

            double left = SystemParameters.VirtualScreenLeft;
            double top = SystemParameters.VirtualScreenTop;
            double width = SystemParameters.VirtualScreenWidth;
            double height = SystemParameters.WorkArea.Height;
            double right = width - Math.Abs(left);
            double bottom = height - Math.Abs(top);

            double afterWidth;
            double afterHeight;

            switch (position)
            {

                case MousePosition.LEFT_BOTTOM:
                    afterWidth = 0;
                    afterHeight = window.Height;
                    break;
                case MousePosition.LEFT_TOP:
                    afterWidth = 0;
                    afterHeight = 0;
                    break;
                case MousePosition.LEFT_CENTER:
                    afterWidth = 0;
                    afterHeight = window.Height / 2;
                    break;
                case MousePosition.RIGHT_BOTTOM:
                    afterWidth = window.Width;
                    afterHeight = window.Height;
                    break;
                case MousePosition.RIGHT_TOP:
                    afterWidth = window.Width;
                    afterHeight = 0;
                    break;
                case MousePosition.RIGHT_CENTER:
                    afterWidth = window.Width;
                    afterHeight = window.Height / 2;
                    break;
                default:
                    afterWidth = window.Width / 2;
                    afterHeight = window.Height / 2;
                    break;
            }

            afterWidth += widthOffset;
            afterHeight -= heightOffset;

            if (p.X - afterWidth < left)
            {
                //判断是否在最左边缘
                window.Left = left - Constants.SHADOW_WIDTH;
            }
            else if (p.X + afterWidth > right)
            {
                //判断是否在最右边缘
                window.Left = right - window.Width + Constants.SHADOW_WIDTH;
            }
            else
            {
                window.Left = p.X - afterWidth;
            }


            if (p.Y - afterHeight < top)
            {
                //判断是否在最上边缘
                window.Top = top - Constants.SHADOW_WIDTH;
            }
            else if (p.Y + afterHeight > bottom)
            {
                //判断是否在最下边缘
                window.Top = bottom - window.Height + Constants.SHADOW_WIDTH;
            }
            else
            {
                window.Top = p.Y - afterHeight;
            }
        }

    }
}