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A scroller is text which scrolls on the status bar of the browser. Take a look at your status bar to see the text scrolling. Scrollers are very popular with JavaScript authors (especially newbies)but are unpopular with the rest of the Web community.
Javascript functions that make the scroller possible:
First is the ability to write to the status bar using
the window.status property like this: The second is the setTimeout() function. This function takes two parameters. The first is a string specifying the JavaScript statement to be executed on triggering and the second is a number specifing time in milliseconds after which triggering occurs. The scroller is essentially a function which, on each invocation, moves the text on the scroll bar a little to the left and then calls setTimeout() to invoke itself after a small interval of time.
Here is the complete code for the scroller.
<SCRIPT LANGUAGE="JavaScript">
<!-- Start of scroller script
var scrollCounter = 0;
var scrollText = "Any text here";
var scrollDelay = 70;
var i = 0;
while (i ++ < 140)
scrollText = " " + scrollText;
function Scroller()
{
window.status = scrollText.substring(scrollCounter++,
scrollText.length);
if (scrollCounter == scrollText.length)
scrollCounter = 0;
setTimeout("Scroller()", scrollDelay);
}
Scroller();
// End of scroller script -->
</SCRIPT>
The only other function we use is substring() which
is a method of the string object. If name="JavaScript",
then name.substring(4,9) will return "Script".
You get the general idea, right?
If programming is not one of your strong points, you can still have the scroller on your page. Just copy the above code into your HTML file, preferably between <HEAD> and </HEAD> tags and change the scrollText and scrollDelay variables in lines 4 & 5 to suit yourself.
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