Let's say there are three fields on the add/edit page: Price, Quantity and Total. To calculate total value on the fly use JavaScript code (add it at the end of the page on the Visual Editor tab in HTML mode).
Here is a sample code for ASPRunnerPro 6.1:
<script>
document.forms.editform.value_Price.onchange = document.forms.editform.value_Quantity.onchange = function()
{
document.forms.editform.value_Total.value = document.forms.editform.value_Price.value*document.forms.editform.value_Quantity.value;
}
</script>
and for ASPRunnerPro 6.2. Add this code to 'Javascript OnLoad' event of the page where you need this calculation to happen:
var ctrlPrice = Runner.getControl(pageid, 'Price');
var ctrlQuantity = Runner.getControl(pageid, 'Quantity');
var ctrlTotal = Runner.getControl(pageid, 'Total');
function func() {
ctrlTotal.setValue(parseFloat(ctrlPrice.getValue()) * parseFloat(ctrlQuantity.getValue()));
};
ctrlPrice.on('keyup', func);
ctrlQuantity.on('keyup', func);