form1.cs

苏金明编写的《用VB.NET和VC#.NET开发交互式CAD系统》一书的源代码

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Drawing.Drawing2D;

namespace IsVisible
{
	/// <summary>
	/// Form1 的摘要说明。
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		/// <summary>
		/// 必需的设计器变量。
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			//
			// Windows 窗体设计器支持所必需的
			//
			InitializeComponent();

			//
			// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
			//
		}

		/// <summary>
		/// 清理所有正在使用的资源。
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{
			this.components = new System.ComponentModel.Container();
			this.Size = new System.Drawing.Size(300,300);
			this.Text = "Form1";
		}
		#endregion

		/// <summary>
		/// 应用程序的主入口点。
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new Form1());
		}

		protected override void OnPaint(PaintEventArgs e)
		{
			Graphics g= e.Graphics;
			g.FillRectangle(Brushes.White, this.ClientRectangle);
			Rectangle rect=new Rectangle(20, 20, 90, 100);
			g.DrawRectangle(Pens.Black, rect);
			g.DrawEllipse(Pens.Black, 150, 100, 100, 100);
		}

		private void Form1_MouseMove(object sender,MouseEventArgs e)
		{
			PointF aPos=new PointF(e.X, e.Y);
			Graphics g = CreateGraphics();
			GraphicsPath gp1=new GraphicsPath();
			GraphicsPath gp2=new GraphicsPath();
			Rectangle rect=new Rectangle(20, 20, 90, 100);
			gp1.AddRectangle(rect);
			gp2.AddEllipse(150, 100, 100, 100);
			Pen p1 =new Pen(Color.Black);
			Pen p2=new Pen(Color.Red);
			Pen p3=new Pen(Color.White);
			p2.DashStyle = DashStyle.Dash;

			if (gp1.IsVisible(aPos))
			{
				g.DrawPath(p3, gp1);
				g.DrawPath(p2, gp1);
			}
			else
			{
				g.DrawPath(p1, gp1);
			}

			if (gp2.IsVisible(aPos))
			{
				g.DrawPath(p3, gp2);
				g.DrawPath(p2, gp2);
			}
			else
			{
				g.DrawPath(p1, gp2);
			}

			gp1.Dispose();
			gp2.Dispose();
			p1.Dispose();
			p2.Dispose();

		}
	}
}