[thelist] Numbers Just Don't Add Up

[Bob Blackman]

I'm experiencing a problem that seems so simple yet I need your help...

In javascript I initialize some variables:

var invoiceOrderTotal = 0;
var invoiceDiscount = 0;
var invoiceSubtotal = 0;
var invoiceShipping = 10;
var invoiceTotal = 10;

I then modify these values:

invoiceOrderTotal += order[rowNum].pulledQty * order[rowNum].salePrice;
invoiceSubtotal = invoiceOrderTotal - invoiceDiscount;
invoiceTotal = invoiceSubtotal + invoiceShipping;

The above works with no problem.  But later when I prepare an invoice,
my values are concatenated rather than summed.  Thus say

invoiceSubtotal = 100.00
invoiceShipping = 10.00
invoiceCOD = 0.00

I get the evaluation of

invoiceTotal = invoiceSubtotal + invoiceShipping + invoiceCOD

Displays 10010.

I have been looking for a method to cast the values as numbers but
haven't come across anything.

Can any of you please help?

Thanks,
Bob