Part 1; a simple slide show: Create a Web document called l5p1.html that displays one of the images from lab 2 in approximately the center of the page; centering need not be exact.

Below the image, place three button elements labeled with the names of items from lab 2. (One of them must be the name of the item you chose to display.) Pressing a button should change the displayed image to that of the item named on the button.

(Hint: There are at least two ways to do this that are discussed in the book. Think about the zIndex: and the visibility: property.) You may use any of these approaches, but please think about all of them. Create a link to this document from your index page.

In no more than a couple of paragraphs, explain which of the possible techniques you chose and why you chose it. Place your write-up below the buttons, on the same page.

Part 2; slide show as sequence: Create a new document, l5p2.html by copying the document from Part 1 and change it so that there's only one button labelled "Next". Each time the button is pressed, the next image must replace the current one.

Pressing the button while the last image is displayed should return the display to the first image and start the cycle over. (Hint: You already have 90% of this done when you have completed Part 1; do not make this hard. Your want to count 0, 1, 2, 0, 1, 2, ... The modulus operator is your friend.) Create a link to this document from your index page.

Think of and describe at least two practical uses for displaying a sequence of images. Write no more than three or four paragraphs in HTML. Place your write-up below the "Next" button.

Part 3; validating form data: Create a new document called l5p3.html. It should have a form with a text input box for an email address and a Submit button.

Submitting the form (either by clicking the button or pressing enter when the button has focus) should call a function that validates the email address.

The function should use a regular expression to validate the email address and return true if valid, or use alert() to display an error message and return false if not.

If the function returns false, the form should not be submitted.

Your regular expression should test for exactly this:

One or more word characters

Exactly one at-sign

One or more word characters

Exactly one period

Two or more characters that are a-z, A-Z, 0-9, period, or hyphen (One way to get "two or more" is to look for one such character and then look for one or more. Don't forget about character classes.)