C#绘制三角形并填充，使用winform实现qq聊天气泡

首先是需求，需要制作一个聊天气泡， 但是winform中有没有类似Android的.9图，只有自己设计图形拼接气泡。

第一种是绘制空心三角形，第二种是绘制三角形区域，可以指定RGB颜色。

private void Form1_Paint(object sender, PaintEventArgs e)
        {
            Pen pen = new Pen(Color.Red, );
            e.Graphics.DrawLine(pen, , , , );
            e.Graphics.DrawLine(pen, , , , );
            e.Graphics.DrawLine(pen, , , , );

            Color color = System.Drawing.Color.FromArgb(((int)(((byte)()))), ((int)(((byte)()))), ((int)(((byte)()))));
            Brush brushes = new SolidBrush(color);
            Point[] point new Point[];
            point[] = new Point(,10);
            point[] = new Point(10,);
            point[] = new Point(10,10);
            e.Graphics.FillPolygon(brushes, point);
        }

效果：

可以作为气泡中的箭头，另外四个角用椭圆：

Winform仿制QQ微信聊天窗口气泡

绘制圆角矩形的代码：

//窗口圆角
private void Main_Paint(object sender, PaintEventArgs e)
        {
            List<Point> list = new List<Point>();
            int width = this.Width;
            int height = this.Height;

            #region 四个圆角

            //左上
            list.Add(new Point(, ));
            list.Add(new Point(, ));
            list.Add(new Point(, ));
            list.Add(new Point(, ));
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            list.Add(new Point(, ));

            //右上
            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));
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            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));
            list.Add(new Point(width - , ));

            //右下
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
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            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));
            list.Add(new Point(width - , height - ));

            //左下
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
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            list.Add(new Point(, height - ));
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            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));
            list.Add(new Point(, height - ));

            #endregion

            Point[] points = list.ToArray();

            GraphicsPath shape = new GraphicsPath();
            shape.AddPolygon(points);

            this.Region = new System.Drawing.Region(shape);

        }