using System; 
using System.Collections; 
using System.Configuration; 
using System.Data; 
using System.Web; 
using System.Web.Security; 
using System.Web.UI; 
using System.Web.UI.HtmlControls; 
using System.Web.UI.WebControls; 
using System.Web.UI.WebControls.WebParts; 
//添加畫圖類 
using System.Drawing.Drawing2D; 
using System.Drawing.Imaging; 
using System.Drawing; 
using System.IO; 
using System.Data.SqlClient; 
public partial class Curve_Default : System.Web.UI.Page 
{ 
protected void Page_Load(object sender, EventArgs e) 
{ 
if (!IsPostBack) 
{ 
Get_CurveData(); 
} 
} 
//獲取數據 
public void Get_CurveData() 
{ 
SqlConnection conn = null; 
try 
{ 
conn = CommonFunction.CreateDBTest(); 
conn.Open(); 
SqlCommand cmd = conn.CreateCommand(); 
string sqlStr = "SELECT * FROM CURVE ORDER BY TESTDATE"; 
DataTable dt = CommonFunction.ExecuteDatable(conn, cmd, CommandType.Text, sqlStr, null); 
draw(dt); 
} 
catch (Exception exp) 
{ 
Response.Write(exp.Message); 
} 
finally 
{ 
if (conn != null) 
conn.Close(); 
} 
} 
public void draw(DataTable dt) 
{ 
//取得記錄數量 
int count = dt.Rows.Count; 
//記算圖表寬度 
int wd = 80 + 20 * (count - 1); 
//設置最小寬度為800 
if (wd < 600) wd = 600; 
//生成Bitmap對像 
Bitmap img = new Bitmap(wd, 400); 
//生成繪圖對像 
Graphics g = Graphics.FromImage(img); 
//定義黑色畫筆 
Pen Bp = new Pen(Color.Black); 
//定義紅色畫筆 
Pen Rp = new Pen(Color.Red); 
//定義銀灰色畫筆 
Pen Sp = new Pen(Color.Silver); 
//定義大標題字體 
Font Bfont = new Font("Arial", 12, FontStyle.Bold); 
//定義一般字體 
Font font = new Font("Arial", 6); 
//定義大點的字體 
Font Tfont = new Font("Arial", 9); 
//定義橫坐標間隔，(最佳值是總寬度-留空寬度[左右側都需要])/(記錄數量-1) 
int xSpace = (wd - 100) / (count - 1); 
//定義縱坐標間隔,不能隨便修改，跟高度和橫坐標線的條數有關，最佳值=(繪圖的高度-上面留空-下面留空) 
int ySpace = 30; 
//縱坐標最大值和間隔值 
int yMaxValue = 30; 
//繪制底色 
g.DrawRectangle(new Pen(Color.White, 400), 0, 0, img.Width, img.Height); 
//定義黑色過渡型筆刷 
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, img.Width, img.Height), Color.Black, Color.Black, 1.2F, true); 
//定義藍色過渡型筆刷 
LinearGradientBrush Bluebrush = new LinearGradientBrush(new Rectangle(0, 0, img.Width, img.Height), Color.Blue, Color.Blue, 1.2F, true); 
//繪制大標題 
g.DrawString("測試曲線圖", Bfont, brush, 40, 5); 
//繪制信息簡報 
string info = " 曲線圖生成時間：" + DateTime.Now.ToString(); 
g.DrawString(info, Tfont, Bluebrush, 40, 25); 
//繪制圖片邊框 
g.DrawRectangle(Bp, 0, 0, img.Width - 1, img.Height - 1); 
//繪制豎坐標軸 
g.DrawLine(Bp, 40, 55, 40, 360); 
//繪制橫坐標軸 x2的60是右側空出部分 
g.DrawLine(Bp, 40, 360, 60 + xSpace * (count - 1), 360); 
//繪制豎坐標標題 
g.DrawString("測試值", Tfont, brush, 5, 40); 
//繪制橫坐標標題 
g.DrawString("測試時間", Tfont, brush, 40, 385); 
//繪制豎坐標線 
for (int i = 0; i < count; i++) 
{ 
g.DrawLine(Sp, 40 + xSpace * i, 60, 40 + xSpace * i, 360); 
} 
//繪制時間軸坐標標簽 
for (int i = 0; i < count; i++) 
{ 
string st = Convert.ToDateTime(dt.Rows[i]["testdate"]).ToString("MM:dd"); 
g.DrawString(st, font, brush, 30 + xSpace * i, 370); 
} 
//繪制橫坐標線 
for (int i = 0; i < 10; i++) 
{ 
g.DrawLine(Sp, 40, 60 + ySpace * i, 40 + xSpace * (count - 1), 60 + ySpace * i); 
//橫坐標軸的值間隔是最大值除以間隔數 
int s = yMaxValue - i * (yMaxValue / 10); 
//繪制發送量軸坐標標簽 
g.DrawString(s.ToString(), font, brush, 10, 60 + ySpace * i); 
} 
//定義縱坐標單位數值=縱坐標最大值/標量最大值（300/30） 
int yAveValue = 10; 
//定義曲線轉折點 
Point[] p = new Point[count]; 
for (int i = 0; i < count; i++) 
{ 
p[i].X = 40 + xSpace * i; 
p[i].Y = 360 - Convert.ToInt32(dt.Rows[i]["testvalue"]) * yAveValue; 
} 
//繪制折線圖 
//g.DrawLines(Rp, p); 
//繪制曲線圖 
//g.DrawCurve(Rp, p); 
//繪制自定義張力的曲線圖（0.5F是張力值，默認就是這個值） 
g.DrawCurve(Rp, p,0.5F); 
//當需要在一個圖里繪制多條曲線的時候，就多定義個point數組，然后畫出來就可以了。 
for (int i = 0; i < count; i++) 
{ 
//繪制發送記錄點的發送量 
g.DrawString(dt.Rows[i]["testvalue"].ToString(), font, Bluebrush, p[i].X, p[i].Y - 10); 
//繪制發送記錄點 
g.DrawRectangle(Rp, p[i].X - 1, p[i].Y - 1, 2, 2); 
} 
//保存繪制的圖片 
MemoryStream stream = new MemoryStream(); 
img.Save(stream, ImageFormat.Jpeg); 
//圖片輸出 
Response.Clear(); 
Response.ContentType = "image/jpeg"; 
Response.BinaryWrite(stream.ToArray()); 
} 
} 
數據表的內容很簡單，就兩個字段：testValue和testDate，由于圖的縱坐標有最大值，所以testValue的值不能超過30，當然，你可以調整坐標軸的單位或者高度。 
12 2008-12-1 0:00:00 
9 2008-12-5 0:00:00 
20 2008-12-10 0:00:00 
18 2008-12-15 0:00:00 
27 2008-12-20 0:00:00 
8 2008-12-25 0:00:00 
15 2008-12-30 0:00:00 
25 2009-1-1 0:00:00 
23 2009-1-5 0:00:00