Generally, you will want to do this in a "Handler" type file. This type =
of file doenst have the overhead that a normal page has, so it is a =
little bit more lightweight. Here is an example of that below. =20

<%@ WebHandler Language=3D"VB" Class=3D"ImgGen" %>

Imports System

Imports System.Web

Imports System.Drawing

Public Class ImgGen : Implements IHttpHandler


Public Sub ProcessRequest(ByVal context As HttpContext) Implements =
IHttpHandler.ProcessRequest

context.Response.ContentType =3D "image/jpeg"


Dim aBitmap As New Bitmap(100, 100, Imaging.PixelFormat.Format32bppArgb)

Dim aBrush As New Drawing2D.LinearGradientBrush(New Point(0, 0), New =
Point(100, 100), Color.Red, Color.Blue)


Graphics.FromImage(aBitmap).FillRectangle(aBrush, 0, 0, 100, 100)


aBrush.Dispose()


aBitmap.Save(context.Response.OutputStream, Imaging.ImageFormat.Jpeg)

End Sub


Public ReadOnly Property IsReusable() As Boolean Implements =
IHttpHandler.IsReusable

Get

Return False

End Get

End Property


End Class



The same code can be used in an ASPX page as well, if you wanted to use =
that as the source. Note that nothing else can be returned via the =
response object except valid image data.



Imports System.Drawing



Partial Class ImgGenInPage

Inherits System.Web.UI.Page

Protected Sub Page_Load(ByVal sender As Object, ByVal e As =
System.EventArgs) Handles Me.Load

Dim aBitmap As New Bitmap(100, 100, Imaging.PixelFormat.Format32bppArgb)

Dim aBrush As New Drawing2D.LinearGradientBrush(New Point(0, 0), New =
Point(100, 100), Color.Red, Color.Blue)

Graphics.FromImage(aBitmap).FillRectangle(aBrush, 0, 0, 100, 100)

aBrush.Dispose()

aBitmap.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

End Sub

End Class



These examples were made using VS2005, so if you are using VS2003, just =
take the code out of it and paste it into VS2003. Some of the example =
will not work, since 2005 uses partial classes.

Let me know if you need more detailed examples.



-Rick






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