实例：asp.net生成曲线图的过程

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());

} }