OnlyOne

Syntax

OnlyOne(fieldlist)

where fieldlist is an arbitrary-length list of fields in the form:

[recordname.]fieldname1 [, [recordname.]fieldname2] ...

Description

Use the OnlyOne function to check a list of fields and return True if one and only one of the fields has a value. If all of the fields are empty, or if more than one of the fields has a value, OnlyOne returns False. This function is used to validate that only one of a set of mutually exclusive fields has been given a value.

A blank character field, or a zero numeric value in a required numeric field is considered a Null value.