这里是从Dataset里的数据生成曲线图.
我的Dataset是从表Sendrec里读取的数据,分别有Id,Sendid(订单号),Sendtime(记录时间),Sendnum(单位时间发送量/我这里是五分钟)几个字段

过程如下:
public void draw(Page page,DataSet ds,int Tnum){}
其中page是用来传递引用这个过程的页面,这样让页面是JPG方式直接向客户端输出生成的曲线图.
ds就是取出来的数据集了
Tnum只是我这里要用到的一个参数,不想让这个类去接触读取过程,所以把订单的总量直接取出后传递给它的.
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Web.UI.HtmlControls;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Drawing;
using System.IO;

public class imgdraw
{
    public imgdraw()
    {
       
    }
    public void draw(Page page,DataSet ds,int Tnum)
    {
        //取得记录数量
        int count = ds.Tables[0].Rows.Count;
        //记算图表宽度
        int wd = 80 + 20 * (count - 1);
        //设置最小宽度为800
        if (wd < 800) wd = 800;
        //生成Bitmap对像
        Bitmap img=new Bitmap(wd,400);
        //生成绘图对像
        Graphics g = Graphics.FromImage(img);
        //定义黑色画笔
        Pen Bp = new Pen(Color.Black);
        //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("Arial", 12, FontStyle.Bold);
        //定义一般字体
        Font font = new Font("Arial", 6);
        //定义大点的字体
        Font Tfont = new Font("Arial", 9);
        //绘制底色
        g.DrawRectangle(new Pen(Color.White, 400), 0, 0, img.Width, img.Height);
        //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);
        //绘制大标题
        g.DrawString(ds.Tables[0].Rows[0]["sendid"].ToString() + "号订单发送情况曲线图", Bfont, brush, 40, 5);
        //取得当前发送量
        int nums=0;
        for (int i = 0; i < count; i++)
        {
            nums+=Convert.ToInt32(ds.Tables[0].Rows[i]["sendnum"]);
        }
        //绘制信息简报
        string info="订单发送时间："+ds.Tables[0].Rows[0]["sendtime"].ToString()+"  曲线图生成时间："+DateTime.Now.ToString()+"  订单总量："+Tnum.ToString()+"  当前发送总量："+nums.ToString();
        g.DrawString(info, Tfont, Bluebrush, 40, 25);
        //绘制图片边框
        g.DrawRectangle(Bp, 0, 0, img.Width - 1, img.Height - 1);

        //绘制竖坐标线      
        for (int i = 0; i < count; i++)
        {
            g.DrawLine(Sp, 40+20 * i, 60, 40+20 * i, 360);
        }
        //绘制时间轴坐标标签
        for (int i = 0; i < count; i+=2)
        {
            string st = Convert.ToDateTime(ds.Tables[0].Rows[i]["sendtime"]).ToString("hh:mm");
            g.DrawString(st, font, brush, 30 + 20 * i, 370);
        }
        //绘制横坐标线
        for (int i = 0; i < 10; i++)
        {
            g.DrawLine(Sp, 40, 60+30*i, 40+20*(count-1), 60+30*i);
            int s = 2500 - 50 * i * 5;
            //绘制发送量轴坐标标签
            g.DrawString(s.ToString(), font, brush, 10, 60 + 30 * i);
        }
       
        //绘制竖坐标轴
        g.DrawLine(Bp, 40, 55, 40, 360);
        //绘制横坐标轴
        g.DrawLine(Bp, 40, 360, 45 + 20 * (count - 1), 360);

        //定义曲线转折点
        Point[] p = new Point[count];
        for (int i = 0; i < count; i++)
        {
            p[i].X = 40 + 20 * i;
            p[i].Y = 360- Convert.ToInt32(ds.Tables[0].Rows[i]["sendnum"]) / 5*3/5;
        }
        //绘制发送曲线
        g.DrawLines(Rp, p);

        for (int i = 0; i < count; i++)
        {
            //绘制发送记录点的发送量
            g.DrawString(ds.Tables[0].Rows[i]["sendnum"].ToString(), font, Bluebrush, p[i].X, p[i].Y - 10);
            //绘制发送记录点
            g.DrawRectangle(Rp, p[i].X - 1, p[i].Y - 1, 2, 2);
        }
        //绘制竖坐标标题
        g.DrawString("发送量", Tfont, brush, 5, 40);
        //绘制横坐标标题
        g.DrawString("发送时间", Tfont, brush, 40, 385);

        //保存绘制的图片
        MemoryStream stream = new MemoryStream();
        img.Save(stream, ImageFormat.Jpeg);
        //图片输出
        page.Response.Clear();
        page.Response.ContentType = "image/jpeg";
        page.Response.BinaryWrite(stream.ToArray());

    }
}
嘿嘿!发表这个,就是一个图片的绘制方法的记录了.这里面还有很多不当之久,望指教.
http://www.cnblogs.com/aowind/archive/2006/11/23/569536.html