Borland Delphi is known to be a great environment for the development of stand-alone and client-server applications on the Microsoft Windows platform. Its virtues range from full OOP support to visual development, in a unique combination of power and ease. However, the new frontier of development is now Internet programming. What has Delphi got to offer in this new context? Which are the features you can rely upon to build great Internet applications with Delphi? That’s what this paper intends to reveal. We’ll see that Delphi can be used:
• For direct socket and TCP/IP programming;
• In conjunction with third-party components that implement the most common Internet protocols, on the client or the server side;
• To produce HTML pages on the server side, with the WebBroker and Internet Express architectures;
• As well as to work with Microsoft’s core technologies, including MTS, COM, ASP, and ActiveX.

The Challenges of Internet Programming
Internet programming poses new challenges to traditional developer environments and to the programmers using them. There are issues related with the implementation of standard protocols, the use of multiple platforms (Microsoft Windows accounts for most of the client computers on the Internet but only a fraction of the servers), and the licensing schemes of some RDBMS systems.

Most of the problems, however, relate with HTTP development:
Turning existing Windows applications into applications running within a Web browser is more complex than it might seem at first sight. The Web is stateless, the development of user interfaces can be quite an issue, and you invariably have to consider the incompatibilities of the most widespread browsers. A new platform specifically aimed at areas of Internet programming (typically the HTTP world) has emerged. These environments favor server side development, often also allowing the inclusion of database information within web pages. A common solution is to write HTML pages with special “scripting” tags included, which are going to be expanded by an engine on the server. Interesting for small projects, most of these technologies have limited scripting power, and force you to mix HTML code and scripting code, and GUI scripting code with database oriented code. On larger applications, this lack of separation among the different areas of a program is considered to be far from a good architecture.

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