Developing Web Applications

Browser Support

In intranet scenarios where a single browser type can safely be assumed, you can design your sites around browser-specific technologies with impunity. (Just in case someone is an errant browser user, you should alert your users with a “Best viewed with” graphic on the site’s home page.)

On the Internet, however, you can’t assume that everyone has an up-to-date browser. And, even among newer browsers, several different types are available; Microsoft, Netscape, and Sun Microsystems have all released browsers with varying degrees of support for ActiveX, Java, scripting, and HTML. The question of what functionality to perform on the client depends on the variety and capabilities of browsers you want to support.

Using the lowest-common-denominator approach, pages contain no more functionality than the least capable browsers can process successfully. Content is guaranteed to be viewable in its entirety on any browser. Unfortunately, users might notice, and be disappointed by, the limited functionality this approach requires.

Some sites provide text-only versions of their pages, or frames-free areas for less capable browsers. This duplication ensures that all users get the same information, but it requires that you develop, test, and maintain multiple versions of your site. Often the less functional version remains underdeveloped, as the focus of development tends toward “bells and whistles.”

The best approach may be to develop pages using basic technology, such as HTML and JavaScript, and to add specific features once you have determined the browser type. This is often a good middle ground, because all pages can be developed using one set of design elements and content. The advanced features of the Web site, such as data binding, are made available only to browsers that support them.

The Browser Capabilities component included in the scripting environment of ASP provides a way to detect the browser type and to tailor the returned document in order to exploit browser-specific capabilities. For more information about this component, see the IIS 5.0 online product documentation.

Table 6.1 summarizes browser support for different client technologies.

Table 6.1   Support for Client Technologies by Browser

© 1997-1999 Microsoft Corporation. All rights reserved.