Objectives - to illustrate some advanced JavaScript programming concepts that include forms, buttons, text boxes, and data verification.
The idea behind this web page is to --
 | show how to build a scrolling message in a text box, and |
| show how to build a form, |
| show how to verify data entered on that form, |
| use the data collected to calculate and display a result. |
The Scrolling Message
| Initial code for the applet -- |
<html> <head> <title>Home Finders Nationwide Realty</title> <!----------------------------------------------> <script language="javascript"> <!--Hide from old browsers
| Scrolling message has 4 components -
| ||||||||
| The logic behind the function is simple: take the message, concatenate the end/start msgSpace (to indicate the end of the message and the beginning), and put it into a text box. | ||||||||
| A recursive call to the function every 200 milliseconds changes the message in the text box by moving the leftmost character to the end of the string, and sliding all the other characters left 1 position | ||||||||
| Here's the code -- |
var scrollMsg = "Mortgage rates are at their LOWEST !!" var msgSpace = "--- ---" var beginPos = 0 function scrollingMsg(){
//
// msgForm - the name we gave to the form containing the textBox
// textBox - the name we gave to the text box on the form
// Both the form and the text box are defined below within the HTML body
//
document.msgForm.textBox.value =
scrollMsg.substring(beginPos,scrollMsg.length)+msgSpace+scrollMsg.substring(0,beginPos)
beginPos = beginPos + 1
if (beginPos > scrollMsg.length) {
beginPos = 0
}
//
// recursive function call to scrollingMsg() using setTimeout
//
window.setTimeout("scrollingMsg()",200)
}
