First time here? First time here? Newsletter Signup Newsletter
Login | Register | 651326 Members and growing!
Search tutorials
Author: Sas Jacobs | Website:


Everything will work fine providing the user enters sensible information in the text fields. Try clicking the Calculate button without entering data and you'll get a strange result. It's a good idea to add validation to form fields before the calculation is carried out so we can avoid this kind of result.

We'll use a dynamic text field to display any errors in the data entered. Add a dynamic text field to the right of the user input fields and give the variable the name ValidationMessage.

Change the CalculateRepayment function to the one shown below. The function tests each of the values and creates an error message if the test is not passed. The repayment amount on the second frame is only displayed if all tests are passed.

function CalculateRepayment(component) {
//do validation
if (intPrincipal <= 0 || intPrincipal == undefined) {
ValidationMessage = "Principal must be a number greater than 0";
else if (floInterest > 100 || floInterest < 1 || floInterest == undefined) {
ValidationMessage = "Annual interest must be between 1 and 100 %";
else if (intTerm <=0 || intTerm == undefined) {
ValidationMessage = "Loan term must be greater than 0";
else if (intRepayments == undefined || intRepayments <=0) {
ValidationMessage = "Please select a repayment period";
else {
//display calculation

You'll also need to add the following line to the first frame of the actions layer. This will clear the validation message text.


» Level Intermediate

Added: 2002-08-07
Rating: 4 Votes: 3
(10 being the highest)
» Author
Applications Developer Marconi Australia
» Download
Download the files used in this tutorial.
» Forums
More help? Search our boards for quick answers!


  • There are no comments yet. Be the first to comment!

  • You must have javascript enabled in order to post comments.

Leave a Comment
  • Your email address will not be published. All fields are required.
Featured Flash FLA
» Author: Inocreato
» Title: RaiseTheBlocks
» Description: Raise all the blocks to win the game
Featured Sound Loops
Image for equalize

Audio Player

» Author: TomCat Carty
» Title: The Wood
» Description: Just a little game ending or it can maybe be looped. Recorders with music box and percussion to give the feel of well, I don't know, the woods? Free to use, just credit me. thank you
Latest Font
» Author: Fábio FAFERS
» Description: I created this font for free use. Everyone can apply it in personal or business texts. Its free, but I want to be communicated in case of business use. Donations are accepted to keep the project of free fonts alive! Thank you all
Featured Sound Fx
Image for equalize

Audio Player

» Author: Davisigner
» Description: Hmm... what to say about this one? It's reminiscent of the closing notes of the opening music from the Three Stooges done in a church organ style with a closing cymbal crash. I'll give this one away gratis, but feel free to check out my free loops and potential upcoming license-mandated ones over in the respective part of Flashkit.