Yet another "Hello World"

This page demonstrates very simple elements of interactive Web applications and explains how they are programmed with heitml.

First, we examine containers and interactive links. A container displays some HTML text that can be changed from a program. There is an example container named myco between the horizontal rulers below.

An interactive link is a link to the same page that executes a little program when it is followed. Click on the Hello World link. Note how the container's text changed to the familiar greeting. Here is another interactive link: reset the container .

Now click on one of the links' handles and press the Extend button in the RADpage window. This shows the program that was executed when you followed the link. It is programmed as a method of the button object. If you don't know what this means you might want to carefully read the following "Hello World" examples that compare the object oriented and the classical programming style. For now, just leave the first and last two line of the action alone. However, if you are somewhat familiar with object-oriented programming, you might want to look at the source code of the current page and examine the class definition of ialink1.

Finally, we combine programming and forms. The following form contains an interactive button. The button's action calculates some text from the form fields and places it in the container.

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