zoukankan      html  css  js  c++  java
  • 鼠标画出矩形

      public partial class ImageLoader : Form
        {

            private Point startPoint, endPoint;
            bool mark = false;
            Graphics bitG;
            Bitmap bits;
            public ImageLoader()
            {
                InitializeComponent();
                picBox1.Dock = DockStyle.Fill;
                bits = new Bitmap(picBox1.Width, picBox1.Height);
                bitG = Graphics.FromImage(bits);
                bitG.Clear(Color.White);
                picBox1.Image = bits;

                picBox1.MouseDown += new MouseEventHandler(picBox1_MouseDown);
                picBox1.MouseMove += new MouseEventHandler(picBox1_MouseMove);
                picBox1.MouseUp += new MouseEventHandler(picBox1_MouseUp);    
            }

            public Rectangle MakeRectangle(Point p1, Point p2)
            {
                int top, left, bottom, right;
                top = p1.X <= p2.X ? p1.X : p2.X;
                left = p1.Y <= p2.Y ? p1.Y : p2.Y;
                bottom = p1.X > p2.X ? p1.X : p2.X;
                right = p1.Y > p2.Y ? p1.Y : p2.Y;
                return (new Rectangle(top, left, bottom - top, right - left));
            }

            private void picBox1_MouseUp(object sender, MouseEventArgs e)
            {
                if (e.Button == MouseButtons.Left)
                {
                    Pen pen1 = new Pen(Color.Black, 1);
                    endPoint = e.Location;
                    Rectangle ret1 = MakeRectangle(startPoint, endPoint);
                    bitG.DrawRectangle(pen1, ret1);
                    picBox1.Image = bits;
                    mark = false;
                }
            }

            private void picBox1_MouseDown(object sender, MouseEventArgs e)
            {
                if (e.Button == MouseButtons.Left)
                {
                    mark = true;
                    startPoint = e.Location;
                    endPoint = e.Location;
                }
               
            }

            private void picBox1_MouseMove(object sender, MouseEventArgs e)
            {
                if (e.Button == MouseButtons.Left && mark)
                {
                    Rectangle ret = MakeRectangle(startPoint, endPoint);
                    ret.Width += 2;
                    ret.Height += 2;
                    picBox1.Invalidate(ret);
                    picBox1.Update();
                    Graphics g = picBox1.CreateGraphics();
                    Pen pen = new Pen(Color.Black, 1);
                    endPoint = e.Location;
                    ret = MakeRectangle(startPoint, endPoint);
                    g.DrawRectangle(pen, ret);
                }
            }

            private void picBox1_Paint(object sender, PaintEventArgs e)
            {
               

            }

         
        }

  • 相关阅读:
    高校招生说明网页被挂马 考生浏览需谨慎 狼人:
    匹配情况hdu4451Dressing
    方法springBean Lifecycle in Spring
    android颜色关于Android TabHost切换Tab字体的颜色背景颜色改变
    推荐美国简单的选项卡功能实现
    按钮function关闭子页面刷新父页面中部分控件数据
    编码文件AndroidStudio初体验:解决Execution failed for task ':TestAndroid:compileDebug'.
    图片类关于实现图片剪切功能的相关类的学习心得
    nullnull10879 Code Refactoring
    java独立HDU 2845 Beans
  • 原文地址:https://www.cnblogs.com/lmcblog/p/2596413.html
Copyright © 2011-2022 走看看