显示指针的位置

Question

我正在尝试实现截屏应用程序，我需要在单击时显示鼠标的位置。

如果您在（鼠标属性-> 指针选项-> 显示指针位置）上启用该选项，我如何显示指针（鼠标）的位置，就像 windows 上默认使用 CTRL 键当我按下 CTRL 键时）

除了在canvas上用故事板画一个圆圈变小然后消失，有什么好的解决办法吗？

Answer 1

您可以使用 Cursor.Position
获取鼠标位置然后你就可以在光标位置画圈了。

因此，如果您需要像 ctrl 场景那样的按键操作，您可以为按键绑定一个事件监听器，或者如果您需要一些常量，您可以在鼠标移动时设置一个事件监听器。

希望对您有所帮助
里昂

Answer 2

一段时间后，我用那个代码做到了。

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;

public static class MouseHook
{
    public class MSLLHOOKSTRUCTEventArgs : EventArgs
    {
        private readonly MSLLHOOKSTRUCT _hookStruct;

        public MSLLHOOKSTRUCTEventArgs(MSLLHOOKSTRUCT hookStruct)
        {
            _hookStruct = hookStruct;
        }

        public MSLLHOOKSTRUCT HookStruct
        {
            get { return _hookStruct; }
        }
    }

    public static event EventHandler<MSLLHOOKSTRUCTEventArgs> MouseDown = delegate { };
    public static event EventHandler<MSLLHOOKSTRUCTEventArgs> MouseUp = delegate { };
    public static event EventHandler<MSLLHOOKSTRUCTEventArgs> MouseMove = delegate { };
    public static bool Started { get; set; }

    static MouseHook()
    {
        Started = false;
    }
    public static void Start()
    {
        Debug.WriteLine("MouseHook.Start");
        _hookID = SetHook(_proc);
        Started = true;
    }

    public static void Stop()
    {
        Debug.WriteLine("MouseHook.Stop");
        UnhookWindowsHookEx(_hookID);
        Started = false;
        MouseDown = null;
        MouseUp = null;
        MouseMove = null;
    }

    private static LowLevelMouseProc _proc = HookCallback;
    private static IntPtr _hookID = IntPtr.Zero;

    private static IntPtr SetHook(LowLevelMouseProc proc)
    {
        IntPtr hook = SetWindowsHookEx(WH_MOUSE_LL, proc, GetModuleHandle("user32"), 0);

        if (hook == IntPtr.Zero)
            throw new System.ComponentModel.Win32Exception();

        return hook;
    }

    private delegate IntPtr LowLevelMouseProc(int nCode, IntPtr wParam, IntPtr lParam);

    private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
    {
        if (nCode >= 0)
        {
            MSLLHOOKSTRUCT hookStruct = (MSLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(MSLLHOOKSTRUCT));
            if (MouseMessages.WM_LBUTTONDOWN == (MouseMessages)wParam)
            {
                if(MouseDown!=null)
                    MouseDown(null, new MSLLHOOKSTRUCTEventArgs(hookStruct));
            }
            else if (MouseMessages.WM_LBUTTONUP == (MouseMessages)wParam)
            {
                if (MouseUp != null)
                    MouseUp(null, new MSLLHOOKSTRUCTEventArgs(hookStruct));
            }
            else
            {
                if (MouseMove != null)
                    MouseMove(null, new MSLLHOOKSTRUCTEventArgs(hookStruct));
            }

        }
        return CallNextHookEx(_hookID, nCode, wParam, lParam);
    }

    private const int WH_MOUSE = 7;
    private const int WH_MOUSE_LL = 14;

    private enum MouseMessages
    {
        WM_LBUTTONDOWN = 0x0201,
        WM_LBUTTONUP = 0x0202,
        WM_MOUSEMOVE = 0x0200,
        WM_MOUSEWHEEL = 0x020A,
        WM_RBUTTONDOWN = 0x0204,
        WM_RBUTTONUP = 0x0205
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct POINT
    {
        public int x;
        public int y;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct MSLLHOOKSTRUCT
    {
        public POINT pt;
        public uint mouseData;
        public uint flags;
        public uint time;
        public IntPtr dwExtraInfo;
    }

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelMouseProc lpfn, IntPtr hMod, uint dwThreadId);

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    private static extern bool UnhookWindowsHookEx(IntPtr hhk);

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);

    [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr GetModuleHandle(string lpModuleName);
}

显示指针的位置

Show location of Pointer

c#

mouse

cursor