Q287 How do I display a random banner image?

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Q287 How do I display a random banner image?

There is an existing JavaScript method that returns a random number:

//Returns a random number between 0 and 1
function getRandom() {
   return Math.random()
}

In Netscape Navigator 2 this only works on Unix platforms, so you might want to try the following instead:

<script>
<!--
// The Central Randomizer 1.3 (C) 1997 by Paul Houle (houle@msc.cornell.edu)
// See:  http://www.msc.cornell.edu/~houle/javascript/randomizer.html

rnd.today=new Date();
rnd.seed=rnd.today.getTime();

function rnd() {
        rnd.seed = (rnd.seed*9301+49297) % 233280;
        return rnd.seed/(233280.0);
};

function rand(number) {
        return Math.ceil(rnd()*number);
};

// end central randomizer. -->
</SCRIPT>

To create a random number between 1 and 10 use rand(10). To display an random image named banner1.gif to banner10.gif use:

<script language="JavaScript"><!--
document.write('<img src="banner' + rand(10) + '.gif" width="400" height="40">');
//--></script>

Feedback on 'Q287 How do I display a random banner image?'

February 25, 2002 at 09:34:27 Cary Foster

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