Using a check box as the basis of calculation

As the MouseUp action of the check-box (let's say it's called CheckBox1) select "Execute JavaScript", and enter the following code:

if (this.getValue("CheckBox1").value=="Yes")
this.getField("Field1").value = this.getField("Field2").value * 10;

Have you looked at How to do (not so simple) form calculations and Conditional Executionby Thom Parker?They will show you how to enter a script into the calculation tab and show how an simple 'if' statement works.

It is even possible to use the simplified field notion, just set the export value of the check box to 1. Be careful about how you name your fields. Assuming your check box is 'CheckBox1' then you code for 'Field1' would be:

Field2 * 10 * CheckBox1

SincFielde the simplified field notation will tread the unchecked value as Zero eve though it is the string 'Off'.

You could even use the option for the 'Field is the product of fields:', if you have a field with a default value of 10.

I would like to revise my advice from earlier... The problem with that approach is that the field (Field1 in this case) doesn't update when Field2 is updated, only when the the box is clicked. Sometimes you want that to happen, but if you don't the way to do it is to use the custom calculation script for Field1 with a code like this:

if (this.getValue("CheckBox1").value=="Yes") {
event.value = this.getField("Field2").value * 10;
} else {
event.value = ""; // or something else, depending on your requirements
}