创建windows窗体应用 ,从工具箱添加Button和Panel

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 绘制面形图
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        Graphics g;//创建Graphics对象
        private void button1_Click(object sender, EventArgs e)
        {
            Bitmap bt = new Bitmap(panel1.Width, panel1.Height);//实例化一个Bitmap对象
            int flag = (panel1.Width - 4) / 6;//X轴的增值
            g = Graphics.FromImage(bt);//实例化Graphics对象
            Pen p = new Pen(Color.Black, 1);//设置Pen对象
            g.DrawLine(p, new Point(0, 0), new Point(0, panel1.Height - 20));//绘制Y轴/从上往下画
            g.DrawLine(p, new Point(0, panel1.Height - 20), new Point(panel1.Width - 4, panel1.Height - 20));//绘制X轴
                                                                                                             //声明一个用于绘制颜色的数组
            Color[] cl = new Color[] { Color.Red, Color.Blue, Color.YellowGreen, Color.Yellow, Color.RoyalBlue, Color.Violet, Color.Tomato };
            int[] points = { 70, 70, 80, 60, 40, 100, 10 };//声明一个计算走势峰值的数组
            Point pt1 = new Point(0, panel1.Height - 20 - points[0]);//记录绘制四边形的第一个点
            Point pt2 = new Point(0, panel1.Height - 20);//记录绘制四边形的第二个点
            for (int i = 0; i <= 6; i++)//通过for循环绘制月份和面形图
            {
                PointF p1 = new PointF(flag * i, panel1.Height - 20);//计算每个月份数字的坐标
                                                                     //绘制显示月份的数字
                g.DrawString(i.ToString(), new Font("宋体", 9), new SolidBrush(Color.Black), new PointF(p1.X - 2, p1.Y));
                //记录绘制四边形的第三个点
                Point pt3 = new Point(flag * i, panel1.Height - 20);
                //记录绘制四边形的第四个点
                Point pt4 = new Point(flag * i, panel1.Height - 20 - points[i]);
                Point[] pt = { pt1, pt2, pt3, pt4 };//声明一个Point数组
                g.FillPolygon(new SolidBrush(cl[i]), pt);//填充四边形的颜色
                                 //当继续绘制下一个四边形时，前一个四边形的最后两个点作为下一个四边形的起始点
                pt1 = pt4;
                pt2 = pt3;
            }
            panel1.BackgroundImage = bt;//显示绘制的面形图
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }
    }
}

   

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