C# 图像处理:实现鼠标选择矩形截图-白红宇

C# 图像处理:实现鼠标选择矩形截图

阅读量：6978 次

发布时间：2019-06-27

本文共 8271 字，大约阅读时间需要 27 分钟。

使用方法如下：

private void button1_Click(object sender, EventArgs e)        {          s.GerScreenFormRectangle();                   }        private Zgke.CopyScreen s;        private void Form1_Load(object sender, EventArgs e)        {            s = new Zgke.CopyScreen();            s.GetScreenImage+=new Zgke.CopyScreen.GetImage(s_GetScreenImage);        }              void s_GetScreenImage(Image p_Image)        {            pictureBox1.Image = p_Image;        }

当按下BUTTON1的时候可以在屏幕上选择一个矩形进行截图

全部的类

先建立个新项目为WINDOWS库类.这里因为需要全局钩子..我在WINFORM里不知道为什么设置不了全局钩子.但在DLL里就可以.....可恶的C#........

复制下面代码到CLASS1.CS里

using System;using System.Collections.Generic;using System.Text;using System.Runtime.InteropServices;using System.Drawing;using System.Windows.Forms;namespace Zgke{    public class API    {        [DllImport("user32.dll", CharSet = CharSet.Auto)]        public static extern IntPtr GetDesktopWindow();        [DllImport("user32.dll", CharSet = CharSet.Auto)]        public static extern IntPtr SetWindowsHookEx(int hookid, HookProc pfnhook, IntPtr hinst, int threadid);        public delegate IntPtr HookProc(int nCode, IntPtr wParam, IntPtr lParam);        [DllImport("kernel32.dll", ExactSpelling = true, CharSet = CharSet.Auto)]        public static extern int GetCurrentThreadId();        [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]        public static extern bool UnhookWindowsHookEx(IntPtr hhook);        public enum WindowsHookCodes        {            WH_MSGFILTER = (-1),            WH_JOURNALRECORD = 0,            WH_JOURNALPLAYBACK = 1,            WH_KEYBOARD = 2,            WH_GETMESSAGE = 3,            WH_CALLWNDPROC = 4,            WH_CBT = 5,            WH_SYSMSGFILTER = 6,            WH_MOUSE = 7,            WH_HARDWARE = 8,            WH_DEBUG = 9,            WH_SHELL = 10,            WH_FOREGROUNDIDLE = 11,            WH_CALLWNDPROCRET = 12,            WH_KEYBOARD_LL = 13,            WH_MOUSE_LL = 14        }    }        ///     /// 一个根据矩形截图类    /// zgke@Sina.com    /// qq:116149    /// 
    public class CopyScreen    {        ///         /// 屏幕大小        /// 
        private Size ScreenSize { get { return Screen.PrimaryScreen.Bounds.Size; } }        ///         /// 鼠标位置        /// 
        private Point MousePoint { get { return Cursor.Position; } }        ///         /// 私有方法获取屏幕图形(全部图形)        /// 
        public Bitmap ScreenImage        {            get            {                                Bitmap m_BackBitmap = new Bitmap(ScreenSize.Width, ScreenSize.Height);                Graphics _Graphics = Graphics.FromImage(m_BackBitmap);                _Graphics.CopyFromScreen(new Point(0, 0), new Point(0, 0), ScreenSize);                _Graphics.Dispose();                return m_BackBitmap;            }        }        ///         /// 钩子        /// 
        private HookMessage m_HookMessage;        ///         /// 屏幕句柄        /// 
        private IntPtr m_ScreenForm;        ///         /// 图形        /// 
        private Bitmap m_Image;        public delegate void GetImage(Image p_Image);        ///         /// 获取屏幕截图        /// 
        public event GetImage GetScreenImage;        ///         /// 构造        /// 
        public CopyScreen()        {            m_ScreenForm = API.GetDesktopWindow();            m_HookMessage = new HookMessage(API.WindowsHookCodes.WH_MOUSE_LL, true);            m_HookMessage.GetHook += new HookMessage.GetHookMessage(m_HookMessage_GetHook);        }        ///         /// 钩子事件        /// 
        ///         ///         ///         ///         void m_HookMessage_GetHook(int p_Code, IntPtr p_wParam, IntPtr p_lParam, ref bool p_Send)        {            if (m_StarMouse)            {                switch (p_wParam.ToInt32())                {                    case 512: //Move                        MouseMove();                        break;                    case 513:  //Down                        MouseDown();                        p_Send = false;                        break;                    case 514:  //Up                        MouseUp();                        p_Send = false;                        break;                    default:                        m_StarMouse = false;                        break;                }            }        }        ///         /// 根据矩形 如果Width是正直接返回 如果使-会转换成正的矩形 保证大小位置不变        /// 
        /// 矩形        /// 
     
      正矩形
             public static Rectangle GetUprightRectangle(Rectangle p_Rectangle)        {            Rectangle _Rect = p_Rectangle;            if (_Rect.Width < 0)            {                int _X = _Rect.X;                _Rect.X = _Rect.Width + _Rect.X;                _Rect.Width = _X - _Rect.X;            }            if (_Rect.Height < 0)            {                int _Y = _Rect.Y;                _Rect.Y = _Rect.Height + _Rect.Y;                _Rect.Height = _Y - _Rect.Y;            }            return _Rect;        }        private Rectangle m_MouseRectangle = new Rectangle(0, 0, 0, 0);        private bool m_DrawStar = false;        private void MouseDown()        {            m_MouseRectangle.X = MousePoint.X;            m_MouseRectangle.Y = MousePoint.Y;            m_DrawStar = true;        }        private void MouseMove()        {            if (m_DrawStar)            {                ControlPaint.DrawReversibleFrame(m_MouseRectangle, Color.Transparent, FrameStyle.Dashed);                m_MouseRectangle.Width = MousePoint.X - m_MouseRectangle.X;                m_MouseRectangle.Height = MousePoint.Y - m_MouseRectangle.Y;                ControlPaint.DrawReversibleFrame(m_MouseRectangle, Color.White, FrameStyle.Dashed);            }        }        private void MouseUp()        {            ControlPaint.DrawReversibleFrame(m_MouseRectangle, Color.Transparent, FrameStyle.Dashed);            m_DrawStar = false;            m_StarMouse = false;            Rectangle _ScreenRectangle = GetUprightRectangle(m_MouseRectangle);            m_MouseRectangle.X = 0;            m_MouseRectangle.Y = 0;            m_MouseRectangle.Width = 0;            m_MouseRectangle.Height = 0;            if (GetScreenImage != null)            {                if (_ScreenRectangle.Width != 0 && _ScreenRectangle.Height != 0) GetScreenImage(m_Image.Clone(_ScreenRectangle, m_Image.PixelFormat));            }        }        private bool m_StarMouse = false;        ///         /// 获取图形        /// 
        public void GerScreenFormRectangle()        {            m_Image = ScreenImage;            m_StarMouse = true;        }        ///         /// 获取图形        /// 
        public void GetScreen()        {            if (GetScreenImage != null) GetScreenImage(ScreenImage);        }    }    ///     /// 用钩子获取消息    /// zgke@Sina.com    /// 
    public class HookMessage    {        private IntPtr m_HookEx;        ///         /// 设置自己进程的钩子        /// 
        /// 钩子类型        public HookMessage(API.WindowsHookCodes p_HookCodes)        {            m_HookEx = API.SetWindowsHookEx((int)p_HookCodes, new API.HookProc(SetHookProc), IntPtr.Zero, API.GetCurrentThreadId());        }        ///         /// 设置进程的钩子        /// 
        /// 钩子类型        /// 全局钩子        public HookMessage(API.WindowsHookCodes p_HookCodes, bool p_Zero)        {            IntPtr _Value = System.Runtime.InteropServices.Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly().GetModules()[0]);            m_HookEx = API.SetWindowsHookEx((int)p_HookCodes, new API.HookProc(SetHookProc), _Value, 0);        }        ///         /// 关闭钩子        /// 
        public void UnHookMessage()        {            if (API.UnhookWindowsHookEx(m_HookEx))            {                m_HookEx = IntPtr.Zero;            }        }        public delegate void GetHookMessage(int p_Code, IntPtr p_wParam, IntPtr p_lParam, ref bool p_Send);        public event GetHookMessage GetHook;        private IntPtr SetHookProc(int p_Code, IntPtr p_wParam, IntPtr p_lParam)        {            GC.Collect();            GC.WaitForPendingFinalizers();            GC.Collect();            bool _SendMessage = true;            if (GetHook != null) GetHook(p_Code, p_wParam, p_lParam, ref _SendMessage);            if (!_SendMessage) return new IntPtr(1);            return IntPtr.Zero;        }    }}