"With ASP.NET you can perform tasks that previously were the domain of ISAPI extensions and filters on IIS with some limitations, but its a lot closer than say ASP was. ISAPI is a low level Win32 style API that had a very meager interface and was very difficult to work for sophisticated applications. Since ISAPI is very low level it also is very fast, but fairly unmanageable for application level development. So, ISAPI has been mainly relegated for some time to providing bridge interfaces to other application or platforms. But ISAPI isnt dead by any means. In fact, ASP.NET on Microsoft platforms interfaces with IIS through an ISAPI extension that hosts .NET and through it the ASP.NET runtime. ISAPI provides the core interface from the Web Server and ASP.NET uses the unmanaged ISAPI code to retrieve input and send output back to the client. The content that ISAPI provides is available via common objects like HttpRequest and HttpResponse that expose the unmanaged data as managed objects with a nice and accessible interface."
Saturday, September 3, 2005 3:47 AM