Dynamically Generate an Image on Part of a Page
You want to create a page that combines a dynamically generated image and ordinary Web controls.
Put the code that generates the dynamic image in a separate page, and create an <img> tag that references the page.
The easiest way to use dynamically generated images with ASP.NET is to write them directly to the response stream. This means that a page that uses a dynamically generated image can’t also use Web controls. One way to circumvent this problem is to create a full-blown custom Web control. Another, simpler option is to use an ordinary HTML <img> tag that references the form that generates the dynamic image.
Figure 15-13 shows one example. On the left are several Web controls ...