need multiple checkboxes to hide/display a text box

This has to be done with JavaScript, and the easiest way to implement it is with a script in single location. For example, the calculation script of the text box, assuming that the check boxes are named "Chk1", "Chk2", and "Chk3"
event.target.hidden = !(this.getField("Chk1").isBoxChecked(0) && this.getField("Chk2").isBoxChecked(0) && this.getField("Chk3").isBoxChecked(0));
The down side of doing it this way is that it's another calculation event. Calculation events are called everytime any field on the form is changed. So another more efficient way to do this(from an operational standpoint) is to put individual testing scripts in the MouseUp events of the check boxes. But this is also more of a hassle and less supportable because you have 3 scripts instead of one.

Thom Parker
The source for PDF Scripting Info
[url=http://www.pdfScripting.com]pdfscripting.com[/url]

The Acrobat JavaScript Reference, Use it Early and Often
[url=http://www.adobe.com/devnet/acrobat/javascript.php]http://www.adobe.com/devnet/acrobat/javascript.php[/url]

will the above code work in the MouseUp events of the checkboxes?

Oh no, that code is specific to the calculation event.

For a mouse up event replace the [b]event.target[/b] with [b]this.getField("MyTextBox")[/b]

Thom Parker
The source for PDF Scripting Info
[url=http://www.pdfScripting.com]pdfscripting.com[/url]

The Acrobat JavaScript Reference, Use it Early and Often
[url=http://www.adobe.com/devnet/acrobat/javascript.php]http://www.adobe.com/devnet/acrobat/javascript.php[/url]

Works perfectly, and here I was trying to use validation sripts in the checkboxes

Thank you so very much. You have saved me from a lot of stress as well as my job!!!!!!!!!!!!!!!

You're welcome, could you mark the tread as answered?