c# 曲线图生成代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.Drawing;
using System.Drawing.Drawing2D;
using System.IO;
using System.Drawing.Imaging;
using System.Collections;

namespace Curve
{
public class CurveDrawing
{
string title, title2, ytitle, xtitle;
/// <summary>
/// X坐标的标题
/// </summary>
public string Xtitle
{
get { return xtitle; }
set { xtitle = value; }
}
/// <summary>
/// Y坐标的标题
/// </summary>
public string Ytitle
{
get { return ytitle; }
set { ytitle = value; }
}
/// <summary>
/// 副标题
/// </summary>
public string Title2
{
get { return title2; }
set { title2 = value; }
}
/// <summary>
/// 主标题
/// </summary>
public string Title
{
get { return title; }
set { title = value; }
}
double yMax, yMin;
List<ArrayList> itemlist;

public CurveDrawing(List<ArrayList> itemlist, string title, string title2 = "")
{
this.itemlist = itemlist;
this.title = title;
this.title2 = title2;

yMax = -100000000;
yMin = 100000000;
for (int i = 0; i < itemlist.Count; i++)
{
if (Convert.ToDouble(itemlist[i][1]) > yMax)
yMax = Convert.ToDouble(itemlist[i][1]);
if (Convert.ToDouble(itemlist[i][1]) < yMin)
yMin = Convert.ToDouble(itemlist[i][1]);
}
}
/// <summary>
/// 创建并输出图片
/// </summary>
/// <returns>生成的文件路径</returns>
public string Draw()
{
#region 基础定义
//取得记录数量
int count = itemlist.Count;

//记算图表宽度
int wd = 80 + 50 * (count - 1);
//设置最小宽度为640
if (wd < 640) wd = 640;
//生成Bitmap对像
Bitmap img = new Bitmap(wd, 400);
//定义黑色画笔
Pen Bp = new Pen(Color.Black);
//加粗的黑色
Pen BBp = new Pen(Color.Black, 2);
//定义红色画笔
Pen Rp = new Pen(Color.Red);
//定义银灰色画笔
Pen Sp = new Pen(Color.Silver);
//定义大标题字体
Font Bfont = new Font("黑体", 12, FontStyle.Bold);
//定义一般字体
Font font = new Font("Arial", 8);
//定义大点的字体
Font Tfont = new Font("Arial", 9);
//定义黑色过渡型笔刷
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, img.Width, img.Height), Color.Black, Color.Black, 1.2F, true);
//定义蓝色过渡型笔刷
LinearGradientBrush Bluebrush = new LinearGradientBrush(new Rectangle(0, 0, img.Width, img.Height), Color.Blue, Color.Blue, 1.2F, true);
LinearGradientBrush Silverbrush = new LinearGradientBrush(new Rectangle(0, 0, img.Width, img.Height), Color.Silver, Color.Silver, 1.2F, true);
#endregion

//生成绘图对像
try
{
using (Graphics g = Graphics.FromImage(img))
{
#region 绘制图表
//绘制底色
g.DrawRectangle(new Pen(Color.White, 400), 0, 0, img.Width, img.Height);
//绘制大标题
g.DrawString(title, Bfont, brush, wd / 2 - title.Length * 10, 5);
//绘制小标题
g.DrawString(title2, Tfont, Silverbrush, wd / 2 - title.Length * 10 + 40, 25);
//绘制图片边框
g.DrawRectangle(Bp, 0, 0, img.Width - 1, img.Height - 1);

//绘制Y坐标线
for (int i = 0; i < (count < 12 ? 12 : count); i++)
g.DrawLine(Sp, 40 + 50 * i, 60, 40 + 50 * i, 360);
//绘制X轴坐标标签
for (int i = 0; i < count; i++)
g.DrawString(itemlist[i][0].ToString(), font, brush, 30 + 50 * i, 370);
//绘制X坐标线
for (int i = 0; i < 11; i++)
{
g.DrawLine(Sp, 40, 60 + 30 * i, 40 + 50 * ((count < 12 ? 12 : count) - 1), 60 + 30 * i);
double s = yMax - (yMax + Math.Abs(yMin)) / 10 * i;//最大的Y坐标值
g.DrawString(Math.Floor(s).ToString(), font, brush, 10, 55 + 30 * i);
}


//绘制Y坐标轴
g.DrawLine(BBp, 40, 50, 40, 360);
//绘制X坐标轴
g.DrawLine(BBp, 40, 360, 40 + 50 * ((count < 12 ? 12 : count) - 1) + 10, 360);

#endregion

#region 绘制曲线
//定义曲线转折点
Point[] p = new Point[count];
for (int i = 0; i < count; i++)
{
p[i].X = 40 + 50 * i;
p[i].Y = 360 - (int)(((Convert.ToDouble(itemlist[i][1]) + Math.Abs(yMin)) / ((yMax + Math.Abs(yMin)) / 10)) * 30);
}
//绘制发送曲线
g.DrawLines(Rp, p);

for (int i = 0; i < count; i++)
{
//绘制发送记录点的数值
g.DrawString(itemlist[i][1].ToString(), font, Bluebrush, p[i].X + 5, p[i].Y - 10);
//绘制发送记录点
g.DrawRectangle(Rp, p[i].X - 2, p[i].Y - 2, 4, 4);
}

#endregion

//绘制Y坐标标题
g.DrawString(ytitle, Tfont, brush, 10, 40);
//绘制X坐标标题
g.DrawString(xtitle, Tfont, brush, 30, 385);
//图片质量
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//保存绘制的图片
string basePath = HttpContext.Current.Server.MapPath("/Curve/"),
fileName = Guid.NewGuid() + ".jpg";

using (FileStream fs = new FileStream(basePath + fileName, FileMode.CreateNew))
{
if (!System.IO.Directory.Exists(basePath))
System.IO.Directory.CreateDirectory(basePath);
img.Save(fs, ImageFormat.Jpeg);
return "/Curve/" + fileName;
}
}

}
catch (Exception)
{
throw;
}

}
}
}