How to divide an Asp.net webform into frames

If you mean IFrames you need to know when to use it. IFrames can be used to display static or some interactive content which is not related to rest of the pages. Say your page is divided into Header, Body and Footer. You want to have common header and footer for all the pages. Then the way is not IFrames. Because if you put Iframe for header, if it interact with the body content it will be a complex problem.

The Asp.net way of dealing with header is master pages or nested master pages. For the footer you can use Web user controls, which you can insert commonly in all the pages.

So summarily IFrames can be use to display static or some interactive content which are not interact with rest of the pages. Web user controls are safer than IFrames in view of scripting vulnerability. But the advantage of IFrames is it can display a remote content.

Or if it needed divide and group the controls in the content page then Panels are the way. You look for multi views if you don't want to show all the contents at same time, but only on certain conditions show that content. Also look at wizard control if you want to create a wizard.

If the above not fit for your question give more details, we would able to help you.

Regards