Idocs Guide to HTML

Rollover Images


You may also want to check out how to create a rollover submit image for a form
"Rollover images" are images that change when the mouse is over them. Rollover Images (or "rollovers" as we'll call them) are popular because they give the image a live feeling... they indicate that something will happen when you click on it. For example, this rollover, which is inside a link, changes from a gray-scale picture to a color picture when the mouse is over it:

Rollovers are really two images: the image when the mouse is over, and another when it's not. Javascript swaps between them when the mouse moves over (onMouseOver) and when it leaves being over (onMouseOut). Our example uses these two images:

Image when the mouse is not over Image when the mouse IS over
Image When The Mouse Is Not Over
Image When The Mouse Is Over
First, copy the following JavaScript into your page. Copy it exactly as-as without making any changes.

<SCRIPT TYPE="text/javascript">
// copyright 1999 Idocs, Inc.
// Distribute this script freely, but please keep this 
// notice with the code.

var rollOverArr=new Array();
function setrollover(OverImgSrc,pageImageName)
if (! document.images)return;
if (pageImageName == null)
    pageImageName = document.images[document.images.length-1].name;
rollOverArr[pageImageName]=new Object;
rollOverArr[pageImageName].overImg = new Image;

function rollover(pageImageName)
if (! document.images)return;
if (! rollOverArr[pageImageName])return;
if (! rollOverArr[pageImageName].outImg)
    rollOverArr[pageImageName].outImg = new Image;
    rollOverArr[pageImageName].outImg.src = document.images[pageImageName].src;

function rollout(pageImageName)
if (! document.images)return;
if (! rollOverArr[pageImageName])return;

This script does most of the work for you. In the next page we'll create the code that implements the scripts for a single rollover image.

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