I have a client that currently has a shopping cart written in ASP that he wants to keep using. We are looking at upgrading the rest of the site to DotNetNuke which is based on ASP.Net.
Does anyone have any guidance on how to use asp pages in an asp.net application? IFrames? I did a little ASP just before dotnet came out, so I"m not that familiar with ASP.
You would be much better off using a single ASP.NET solution.
There is a DNN shopping cart module available from here. There is supposed to be a community edition. [I haven't used it, so can't say how good it is]
You can combine them pretty easily, you will just need to have the asp have its own global.asa and session timing. As long as your authentication logic is simple, you can write it in both, or consume it as a service from the asp pages.
The main concerns are shared state amongst pages. IFrames are viable options, but hard to get to look natural.
I'm currently doing this in an application that is half converted, its 170 aspx pages, and 210 asp pages.
That said, the context switching of maintaining both parts, is painful. So try and get it rewritten, quickly. On MVC its fairly trivial to have the logic flow like asp.
You can mix the two, but I don't think you'll be able to do things like share state between them unless you cater for this with a third party provider. They'll behave more like two "seperate" sites.
One other thing worth mentioning is that if you are provisioning a new web server for the mix, and planning to pull in the old ASP code, is that ASP is not enabled default on the more recent versions of IIS.
You can't use ASP pages in an ASP.NET application.
You can have an ASP application and an ASP.NET application in the same web site, but they are still two different applications. They work side by side, basically unaware of each other.
You can have the pages communicating with each other, and even use iframes to seamingly mix them in the same page, but communication is not trivial as the web applications can't communicate directly. You can communicate between them on the client side, or through a common backend database (or any other indirect way that you can think of...).
Most asp is going to valid as asp.net. You may be able to rename your .asp pages to .aspx and get 80-90% of the old code working under asp.net. Then fix anything that's broken and slowly migrate more and more of the old code to proper asp.net.