How Netscape Provides Browser-Specific Content

Now we've covered just about everything you need to know to understand how Netscape serves up the browser-specific content illustrated at the beginning of the chapter (Figure 3-1 and Figure 3-2). Here is a somewhat simplified and modified version of the JavaScript on Netscape's home page:

<script type = "text/javascript"> ❶ var agent = navigator.userAgent.toLowerCase(); ❷ var major = parseInt(navigator.appVersion); var minor = parseFloat(navigator.appVersion); ❸ var ns = ((agent.indexOf('mozilla') != −1) && (agent.indexOf('compatible') == −1)); ❹ var ns4 = (ns && (major == 4)); var ns7 = (ns && (agent.indexOf('netscape/7') != −1) ); var ie = (agent.indexOf("msie") != −1); var ie4 = (ie && (this.major ...

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