InfoPath Dev

It is very easy to set a text box with a value by using Rules. However, all these rules are called with change on a control or click on a button. I want to set a text box with a boolean value when the form is opened.  Then I'll use this value to set conditional format for some controls such as visible or enabled. How can this text box  value be initialized when the form is opened? Thanks for any help!

 By the way, I am using InfoPath 2003.
 

When in design mode go to Tools on the Menu Bar

Select Form Options

Select the Open and Save tab

Select Rules.

These Rules will be processed when the form opens and before the default view is displayed. Allowing you to change the view or set variables depending on conditions.