Displaying random text on a web page using JavaScript - 2

Now that you know how to randomly display text, we'll see how we can display this text as a marquee (using the <MARQUEE> tag) in Internet Explorer or make this text blink (using the <BLINK> tag in Netscape Communicator).

The first step is to make a browser detection script. Depending on the browser, we execute the appropriate document.write() method.

The browser detention script use the appName property of the navigator object.

<SCRIPT LANGUAGE="JAVASCRIPT">
<!--

var r_text = new Array ();
r_text[0] = "All the leaves are brown";
r_text[1] = "And the sky is grey";
r_text[2] = "I've been for a walk";
r_text[3] = "On a winter's day";
r_text[4] = "I'd be safe and warm";
r_text[5] = "If I was in L.A.";
r_text[6] = "California dreaming, On such a winter's day";

var i = Math.floor(7*Math.random());

if (navigator.appName == "Netscape")
   {
   document.write("<BLINK><FONT COLOR='
   #FF0000'>" + r_text[i] + "</FONT></BLINK>");
   }
else
   {
   document.write("<MARQUEE><FONT COLOR='#FF0000'>" +
   r_text[i] + "</FONT></MARQUEE>");
   }

//-->
</SCRIPT>

Remember, JavaScript arrays are zero indexed (the first element of an array in JavaScript has an index of 0). Our array r_text consists of seven elements.
The Math.random() method returns a value between 0 and 1. We have to convert this value to an integer between 0 to 6 so that it can be used as an index to retrieve the string from the r_text array. We store the final value in a variable i.

The Result
Click on the refresh button to see another text string below.