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You need to create your own Validation Script. You can do this by going to the Text Field Properties Box.
Go to the Validate Tab, check Run Custom Validation Script, then click the Edit Button.
In the JavaScript Editor, type in your JavaScript.
Section 5.6: Tab Order
Now that all of your form fields have been completed, you need to test the tab order of your PDF. A user may not be able to use the mouse to click from one form field to another. A good alternative to access the form fields is by using the Tab Key. To test your PDF, click the Preview Button and hit the Tab Key several times. What should happen is that the first form field at the top of the PDF should be highlighted first. Then by clicking the Tab Key again, the form next to or underneath the first form field will be highlighted. If a form field is skipped, that means the Tab Order is out of order. To fix the Tab Order,
Go into the Prepare Form Tool Edit Mode.
On the right side of the screen, go to the Fields Section.
The Fields Section contains all of your form fields and gives you the ability to rearrange the order of the form fields. To move the form field order, click and drag the field you want into a new position.
Go back to Preview Mode and press the Tab Key to test the new location of your form fields.
Keep tweaking the Fields Section until everything is in order.
Section 5.15: PDF Form Wizard
The Form Wizard scans your form and automatically add fields for you.
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