Hour 14. ATL Servers

The Active Template Library (ATL) Server is a new technology within Visual C++ .NET not present in previous versions of Visual Studio. ATL Server is a server-based technology that runs on the Internet Information Services (IIS) Web server platform. It plays a dual role within the .NET Framework, having the ability to create Web Services, as you saw in Hour 11, "Creating Web Services," as well as Web applications, the topic of this hour.

ATL Server uses a tag-replacement methodology similar to the way ASP.NET functions. In other words, a certain tag (otherwise known as a replacement tag, consisting of a string of characters enclosed within two curly braces on each end) is encountered by the Web server (IIS), and rather than that tag being passed directly to the rendering stream, it is handed off to an extension DLL. This extension DLL then replaces the tag with its own content, which is then passed down to be rendered on the client Web browser.

In this hour you will learn:

• How to create an ATL Server project and what options are available for your project

• What a server response file (SRF) is and the syntax necessary to interact with your extension DLL

• How to specify new replacement tags within your extension DLL and how to render to the response stream