C#实现图形区域组合操作的方法

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;namespace advanced_drawing{  public partial class Form17 : Form  {    public Form17()    {      InitializeComponent();    }    private void Form17_Paint(object sender, PaintEventArgs e)    {      Rectangle regionRect = new Rectangle(20, 20, 100, 100);      e.Graphics.DrawRectangle(Pens.Black, regionRect);      RectangleF unionRect = new RectangleF(90, 30, 100, 100);      e.Graphics.DrawRectangle(Pens.Red, Rectangle.Round(unionRect));      Region myRegion = new Region(regionRect);      //myRegion.Union(unionRect);      //myRegion.Intersect(unionRect);      //myRegion.Exclude(unionRect);      //myRegion.Complement(unionRect);      myRegion.Xor(unionRect);      SolidBrush myBrush = new SolidBrush(Color.Blue);      e.Graphics.FillRegion(myBrush, myRegion);    }  }}