c#如何利用鼠标绘制多边形

Question

在窗体里面设置一个画布，然后在画布里面用鼠标左键收集点，右键表示多边形绘制完成。

Answer 1

写了个示例，对你有帮助能点击采纳支持下吗，谢谢~ 效果如下

        List<Point> polyPoints = null;
        bool cliceMenu = false;
        private void Form1_MouseDown(object sender, MouseEventArgs e)
        {
            if (cliceMenu)
            {
                if (e.Button == MouseButtons.Left)
                {
                    if (polyPoints == null) polyPoints = new List<Point>();
                    polyPoints.Add(e.Location);
                }
                else if (e.Button == MouseButtons.Right)
                {
                    using (var g = this.CreateGraphics())
                    {
                        g.SmoothingMode = SmoothingMode.AntiAlias;
                        g.Clear(Color.White);

                        using (SolidBrush br = new SolidBrush(Color.FromArgb(100, Color.Yellow)))
                        {
                            g.FillPolygon(br, polyPoints.ToArray());
                        }
                        g.DrawPolygon(Pens.DarkBlue, polyPoints.ToArray());

                        foreach (Point p in polyPoints)
                        {
                            g.FillEllipse(Brushes.Red,
                                                   new Rectangle(p.X - 2, p.Y - 2, 4, 4));
                        }


                        polyPoints = null;
                    }
                }
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            using (var g = this.CreateGraphics())
            {
                g.Clear(this.BackColor);
            }
        }

        private void 绘制多边形ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            cliceMenu = true;
        }

        private void 停止绘图ToolStripMenuItem_Click(object sender, EventArgs e)
        {

            cliceMenu = false;
        }