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Enhancing Text Readability Online Through Code

Text readability is an extremely important part of any web site, but how do you know what size your users will find readable? Kris Hadlock shows you how to solve this problem by creating a text-zooming component with JavaScript. This component not only enables users to resize the text on your web site but it also enables you to restrict what text they can resize.
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The Web is the most efficient way to distribute information to the largest amount of people in the shortest period of time. Any time you have a large group of people, you usually have some diversity. Diversities are important to keep in mind if you care about your application’s users. For example, age can play a huge role in a user’s vision and, while it may look better to have smaller fonts on your web site, some users might not be able to read a damn thing.

In this article, we’ll take a look at how to enhance text readability through code by developing a JavaScript component for text zooming. This component enables users to dynamically increase or decrease the size of the text in the areas in which we allow it. We’ll also have the ability to maintain an initial text size for design aesthetics and restrict the enlarging to a reasonable font size. A live sample can be viewed here and the source code for the article can be downloaded here.

Getting Started

The first thing that we need to create is a simple HTML file that will demonstrate text a user could be viewing on our web site. The example that we’ll create will include a title and a couple of paragraphs of descriptive text.

Our sample page will start with a simple page border that will act as a container for the text we’ll be adding. The first piece of text is a bold title that contains style properties for its font size and line height and an id named title. After the title, we’ll add a couple of paragraphs of descriptive text to a div and give it an id named description. Just like the title, the description will also contain style properties for the font size and line height, which will act as our default sizes.

Creating a Sample Page (index.html)

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<title>InformIT: Enhancing Text Readability Through Code</title>


<div style="width: 500px; padding: 20px; border: 1px #333 solid;">
    <b id="title" style="font-size: 18px; line-height: 24px;">Enhancing Text Readability Through Code</b>
    <div id="description" style="width: 500px; font-size: 11px; line-height: 18px;">
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