Question

我被要求做一个能够做这样的事情的应用程序（最好用C＃）：

我运行应用程序（例如：它在我的活动监视器上处于活动状态）
然后我点击2个像素（不一定是像素，epsilon将是+ -3px）
程序会在底部计算或显示它们之间的高度（宽度）

像＆＃34; positionShower＆＃34;在一个简单的绘画中，除了我在整个显示屏上选择2个像素（如果它在活动窗口中或完全不在它之外并不重要）但它不需要运行任何其他程序在同一时间。

有任何帮助吗？我真的无法搜索任何类似的东西。

Answer 1

    int distance;
    Point location = new Point(); 
    Point location2 = new Point();
    private void FormClick(object sender, EventArgs e)
    {

        if(location == new Point())
        {
            location = Form.MousePosition;
        }
        else if (location2 == new Point())
        {
            location2 = Form.MousePosition;
            distance = location2.X - location.X;
            location = new Point();
            location2 = new Point();
        }
    }

Answer 2

要执行此操作，您需要将低级鼠标事件全局挂钩，请参阅示例代码中的LowLevelMouseProc，SetWindowsHookEx和其他函数。

要测试示例，请创建一个新的Windows窗体项目，并在主窗体上添加三个标签，如下所示：

form design

并使用以下内容替换Form1.cs中的代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            _proc = HookCallback;

            _hookID = SetHook(_proc);

        }

        // This method is called for each global mouse event
        private IntPtr HookCallback(
            int nCode, IntPtr wParam, IntPtr lParam)
        {
            if (nCode >= 0 &&
                MouseMessages.WM_LBUTTONDOWN == (MouseMessages)wParam)
            {
                MSLLHOOKSTRUCT hookStruct = (MSLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(MSLLHOOKSTRUCT));
                if (isFirstClick)
                {
                    firstClickMouseStruct = hookStruct;
                    label1.Text = "First click: " + hookStruct.pt.x + ", " + hookStruct.pt.y;
                }
                else
                {
                    secondClickMouseStruct = hookStruct;
                    label2.Text = "Second click: " + secondClickMouseStruct.pt.x + ", " + secondClickMouseStruct.pt.y;
                    label3.Text = "Height: " + Math.Abs(secondClickMouseStruct.pt.y - firstClickMouseStruct.pt.y)
                        + ", Width: " + Math.Abs(secondClickMouseStruct.pt.x - firstClickMouseStruct.pt.x);
                }
                isFirstClick = !isFirstClick;
            }
            return CallNextHookEx(_hookID, nCode, wParam, lParam);
        }

        private MSLLHOOKSTRUCT firstClickMouseStruct;
        private MSLLHOOKSTRUCT secondClickMouseStruct;
        private bool isFirstClick = true;

        private LowLevelMouseProc _proc = null;
        private IntPtr _hookID = IntPtr.Zero;

        private IntPtr SetHook(LowLevelMouseProc proc)
        {
            using (Process curProcess = Process.GetCurrentProcess())
            using (ProcessModule curModule = curProcess.MainModule)
            {
                return SetWindowsHookEx(WH_MOUSE_LL, proc,
                    GetModuleHandle(curModule.ModuleName), 0);
            }
        }

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

        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)]
        private struct POINT
        {
            public int x;
            public int y;
        }

        [StructLayout(LayoutKind.Sequential)]
        private 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);

        private void Form1_FormClosed(object sender, FormClosedEventArgs e)
        {
            UnhookWindowsHookEx(_hookID);
        }
    }
}

现在，您可以在表单内部或外部（桌面或其他窗口）上单击鼠标左键，应用程序将挂钩点击，检查鼠标位置并根据需要计算高度和宽度：

result

如何计算屏幕上2个像素之间的高度（宽度）？

2 个答案: