View Menu

Technical Support Forums

Free, outstanding support from WebAssist and your colleagues

Javascript to sum drop down values

Thread began 5/17/2009 10:12 am by rdubill357341 | Last modified 5/20/2009 10:27 am by rdubill357341 | 13554 views | 5 replies


Javascript to sum drop down values

Ray - I'm close but one problem remains:

Here's my HTML:

<input type="text" id="totalcost" value="" />
<select name="prod0" id="prod0" onchange="MM_callJS('UpdateCost()')" >
<option value="100.00">one</option>
<option value="200.00">two</option>

The script:

function UpdateCost() {
var sum = 0;
var gn, elem;
for (i=0; i<29; i++) {
gn = 'prod'+i;
var dropdownIndex = document.getElementById(gn).selectedIndex;
var dropdownValue = document.getElementById(gn)[dropdownIndex].value;
{ sum += Number(dropdownValue); }
document.write('totalcost').value = sum.toFixed(2);

The values are being selected correctly - I verified that by testing a document.write statement and 'dropdown value' displays with the correct value...

The last statement in the script does not display the 'totalcost'...

Are the values not being 'summed' correctly from the drop down list?

Is the document.write statement for totalcost not correct?

Is the sum of the values not being added to totalcost?

Any help you can provide is much appreciated - this is the last item for this project I need to get working before publishing...

Build websites with a little help from your friends

Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.

Build websites from already-built web applications

These out-of-the-box solutions provide you proven, tested applications that can be up and running now.  Build a store, a gallery, or a web-based email solution.

Want your website pre-built and hosted?

Close Windowclose

Rate your experience or provide feedback on this page

Account or customer service questions?
Please user our contact form.

Need technical support?
Please visit support to ask a question





Ease of use


security code refresh image

We do not respond to comments submitted from this page directly, but we do read and analyze any feedback and will use it to help make your experience better in the future.

Close Windowclose

We were unable to retrieve the attached file

Close Windowclose

Attach and remove files

add attachmentAdd attachment
Close Windowclose

Enter the URL you would like to link to in your post

Close Windowclose

This is how you use right click RTF editing

Enable right click RTF editing option allows you to add html markup into your tutorial such as images, bulleted lists, files and more...

-- click to close --

Uploading file...