Web Applications
Overview
So far this website has covered web-servers, website design, webpage coding, JS and DHTML and CGI scripting in some detail giving you everything that you will need to write efficient and maintainable standards based websites.
The time has now come to put all of these ideas into practice.
Our previous application example; 'Temperature Converter' was necessarily a simple one and served only as a 'vehicle' to drive the new ideas being shown. However using the exact same ideas and principles we can go on to develop far more sophisticated and useful applications.
Below are a number of working applications. In most cases there are detailed accompanying notes, source code views and the many of the programs are available for your own use, after all another key design factor is portability.
Some of the programs are 'related', that is to say that they share similar core features, one program will often serve as the foundation for the next one. All of the programs use the basic framework and methods outlined in all of the previous examples.
- getpage.pl - Get Page
Read program notes... — »Run application... — »View source code...
This program will display a simple form which invites you to enter a URL. On submission the program willGETthe requested page and display its source code.
Strictly speaking this is not a useful application as it stands, however it is a precursor to so many other programs that require pages to be fetched across the 'net. Once the source code of a page has been fetched it can be parsed in many ways. The most obvious use is as a spider, all of the links to other pages are located and added to a list to be scanned. The page source code can also be passed to an analyser, perhaps to check the code, build keyword lists and so on, the list of possibilities is endless.