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Creating a vertical content scroller using DHTML

This tutorial written and contributed by John at Dynamicdrive.com

In this tutorial, I'll show you how to create a vertical content scroller using DHTML. A content scroller is a little different from traditional JavaScript scrollers in that the content to scroll is simply regular HTML on the page. The advantage of this is obvioius- ease of customization, and also, search engine friendly. Below's a demonstration of what I'll be building:

Example:

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The HTML

Lets first see the CSS and HTML that make up the foundation of the scroller, before seeing the script itself:

<style type="text/css">

#marqueecontainer{
position: relative;
width: 200px; /*marquee width */
height: 200px; /*marquee height */
background-color: white;
overflow: hidden;
border: 3px solid orange;
padding: 2px;
padding-left: 4px;
}

</style>

<body>

<div id="marqueecontainer" onMouseover="copyspeed=pausespeed" onMouseout="copyspeed=marqueespeed">
<div id="vmarquee" style="position: absolute; width: 98%;">

<!--YOUR SCROLL CONTENT HERE-->

<h4>Your scroller contents</h4>

<!--YOUR SCROLL CONTENT HERE-->

</div>
</div>

Here I define an outer DIV (ID="marqueecontainer") and set its position to "relative" inside the CSS. A relative positioned element defines a new coordinates system for anything contained inside, with the upper left corner of the element being (0, 0). This makes it easy to then define an absolutely positioned DIV (ID="vmarquee"), and scroll it upwards relative to the outer DIV.

With the basic framework of the scroller created, lets now see the script that will scroll the DIV (ID="vmarquee") upwards to create a vertical content scroller.