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用ASP.NET动态生成图像（转2）

出处:互联网   整理: 软晨网（RuanChen.com）   发布: 2009-11-03   浏览: 99 ::
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StockPicker.aspx:
<script language="VB" runat=server>
Sub ChartBtn_Click(Sender as Object, E as EventArgs)
chart.ImageUrl = "ImageGenerator_Vb.aspx?"
chart.Visible = true
For i=0 to Stocks.Items.Count-1
If (Stocks.Items(i).Selected = true) Then
chart.ImageUrl = chart.ImageUrl & "symbols=" & Stocks.Items(i).Value & "&"
End If
Next
End Sub
</script>
<html>
<body>
<form runat=server>
<h1>Scott's Stock Picker</h1>
<asp:checkboxlist id="Stocks" runat=server>
<asp:listitem>MSFT</asp:listitem>
<asp:listitem>SUN</asp:listitem>
</asp:checkboxlist>
<asp:button text="Chart Your Selected Stocks" OnClick="ChartBtn_Click" runat=server/>
<hr>
<asp:Image id="chart" ImageUrl="" Visible=false runat=server/>
</form>
</body>
</html>

ImageGenerator_VB.aspx:
<%@ Page Language="VB" ContentType="image/jpeg" %>
<%@ Import Namespace="System.Drawing" %>
<%@ Import Namespace="System.Drawing.Drawing2D" %>
<%@ Import Namespace="System.Drawing.Imaging" %>
<%@ Import Namespace="ChartGenerator" %>
<%@ OutputCache Duration="10" %>
<script language="VB" runat=server>
Function GetStockDetails(Symbol as String) as ChartLine
Dim myChartLine as new ChartLine
if (symbol = "msft") then
Dim StockValues() as Single = { 60, 110, 120, 180, 185, 190, 240, 290 }
myChartLine.Width = 5
myChartLine.Color = Color.Blue
myChartLine.LineStyle = DashStyle.Solid
myChartLine.Title = "Microsoft Corp. (MSFT)"
myChartLine.Symbol = "MSFT"
myChartLine.Values = StockValues
return myChartLine
elseif (symbol = "sun") then
Dim StockValues() as Single = { 180, 155, 125, 60, 25, 15, 10, 3 }
myChartLine.Width = 5
myChartLine.Color = Color.Red
myChartLine.LineStyle = DashStyle.Dot
myChartLine.Title = "Sun Corp. (Sun)"
myChartLine.Symbol = "Sun"
myChartLine.Values = StockValues
return myChartLine
end if
return nothing
End Function
Sub Page_Load(Sender as Object, E as EventArgs)
' Generate Chart Data For Image....
Dim XAxes() as String = { "9:00AM", "9:30AM", "10:00AM", "11:00AM", "12:00AM", "1:00PM", "1:30PM" }
Dim MyChartData as New ChartData
MyChartData.YTickSize = 20
MyChartData.YMax = 250
MyChartData.YMin = 0
MyChartData.XAxisTitles = XAxes
Dim Symbols() as String = Request.QueryString.GetValues("symbols")
if (Not Symbols = Nothing) then
for i=0 to Symbols.Length-1
Dim stockValue as ChartLine = GetStockDetails(symbols(i).ToLower)
If (stockValue <> nothing) then
myChartData.Lines.Add(stockValue)
End if
Next
end if
' Create In-Memory BitMap of JPEG
Dim MyChartEngine as New ChartEngine
Dim StockBitMap as BitMap = MyChartEngine.DrawChart(600, 400, myChartData)
' Render BitMap Stream Back To Client
StockBitMap.Save(Response.OutputStream, ImageFormat.JPEG)
End Sub
</script>

ChartEngine.cs:
using System.WinForms;
using System.Collections;
using System.Collections.Bases;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.ComponentModel;
using System;
using System.IO;
namespace ChartGenerator {
//Core Line Data structure
public struct LineData {
public float[] LineValues ;
public string LineTitle ;
public string LineSymbol ;
}

//Line Data plus display style information
public class ChartLine {
private Color lineColor ;
private LineData lineData ;
private DashStyle lineStyle ;
private int lineWidth ;
//Constructors
public ChartLine() :base() {}
public ChartLine(LineData lineData) :base() {
this.lineData = lineData;
}
//Properties
public Color Color {
get { return lineColor ; }
set { lineColor = value ; }
}
public DashStyle LineStyle {
get { return lineStyle ; }
set { lineStyle = value ; }
}

public st