Field Calculations in Locked Forms

Subscriber Kathleen Mayfield wrote about a problem she was having with Word not updating a calculated field in a locked form. For instance, if there are three fields (Field1, Field2, and Field3) that are summed together into another field (Total), then Kathleen could not get the Total field to calculate, even though she set the Calculate on Exit property of the Total field.

The reason the problem occurs is a misunderstanding of the way in which Word calculates form fields; it has nothing to do with the fact that the form is locked. (In fact, the form must be locked in order to fill in the form fields at all.) The problem arises because it is not the Total field that must have the Calculate on Exit property turned on, but the fields on which Total is dependent. In this instance all three contributory fields--Field1, Field2, and Field3--must have their Calculate on Exit property set. If they do, then the Total will update properly (and interactively) as expected.

As a side note, it does very little good to have the Calculate on Exit property set in the Total field. Why? Because when you set the field's Type property to Calculation, enter your formula in the Form Field Options dialog box, and then lock the form, the Total field cannot be selected. If it cannot be selected, you can't exit it (you can't exit what you can't enter), so the Calculate on Exit property is never triggered.