(深入.Net平台和C#编程)第六章.简答题5.20170410

-------------------------------------------父类形状类-------------------------------------------

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace J4.entity
{
    public class Shape
    {
        public virtual void Draw(Graphics g, Pen p)
        {
        }
    }
}

-------------------------------------------子类圆形类-------------------------------------------

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace J4.entity
{
    public class Circle:Shape
    {
        public override void Draw(Graphics g, Pen p)
        {
            g.DrawEllipse(p, 75,150,100,100);
        }

      
    }
}

-------------------------------------------子类矩形类-------------------------------------------

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace J4.entity
{
   public class Rect:Shape
    {
       public override void Draw(Graphics g, Pen p)
       {
           Rectangle rec = new Rectangle(20, 100, 200, 200);
           g.DrawRectangle(p, rec);
       }
    }
}

-------------------------------------------主窗体类-------------------------------------------

using J4.entity;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace J4
{
    public partial class frmMain : Form
    {
        public frmMain()
        {
            InitializeComponent();
        }

        private void btnDraw_Click(object sender, EventArgs e)
        {
            //Graphics g = CreateGraphics();
            ////(颜色,厚度)
            //Pen p = new Pen(Color.Red,3);
            ////(X轴坐标,Y轴坐标,宽,高)
            //Rectangle rec = new Rectangle(50,100,200,200);
            ////矩形
            //g.DrawRectangle(p,rec);
            ////圆形
            //g.DrawEllipse(p,50,100,100,100);



            Shape shape = new Shape();
            Graphics g = this.panel1.CreateGraphics();
            //默认红色
            Pen p = new Pen(Color.Red, 3);

            //判断选中的是什么形状
            if (rbtnCircle.Checked == true)
            {
                shape = new Circle();
            }
            else
            {
                shape = new Rect();
            }
            //判断选中的是什么颜色
            if (rbtnBlue.Checked == true)
            {
                p = new Pen(Color.Blue, 3);
            }
            else if (rbtnYellow.Checked == true)
            {
                p = new Pen(Color.Yellow, 3);
            }
            //调用方法
            shape.Draw(g,p);
            
        }

        private void panel1_Paint(object sender, PaintEventArgs e)
        {
        }
    }
}