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Field2.ValidationRule Property

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Access Developer Reference

Sets or returns a value that validates the data in a field as it's changed or added to a table (Microsoft Access workspaces only). Read/write String.

Syntax

expression.ValidationRule

expression   An expression that returns a Field2 object.

Remarks

The settings or return values is a String that describes a comparison in the form of an SQL WHERE clause without the WHERE reserved word. For an object not yet appended to the Fields collection, this property is read/write.

The ValidationRule property determines whether or not a field contains valid data. If the data is not valid, a trappable run-time error occurs. The returned error message is the text of the ValidationText property, if specified, or the text of the expression specified by ValidationRule.

For a Field2 object, use of the ValidationRule property depends on the object that contains the Fields collection to which the Field2 object is appended.

Object appended to Usage
Index Not supported
QueryDef Read-only
Recordset Read-only
Relation Not supported
TableDef Read/write

Validation is supported only for databases that use the Microsoft Access database engine.

The string expression specified by the ValidationRule property of a Field2 object can refer only to that Field2. The expression can't refer to user-defined functions, SQL aggregate functions, or queries. To set a Field2 object's ValidationRule property when its ValidateOnSet property setting is True, the expression must successfully parse (with the field name as an implied operand) and evaluate to True. If its ValidateOnSet property setting is False, the ValidationRule property setting is ignored.

Bb257465.vs_note(en-us,office.12).gif  Note
If you set the property to a string concatenated with a non-integer value, and the system parameters specify a non-U.S. decimal character such as a comma (for example, strRule = "PRICE > " & lngPrice, and lngPrice = 125,50), an error will result when your code attempts to validate any data. This is because during concatenation, the number will be converted to a string using your system's default decimal character, and Microsoft Access database engine SQL only accepts U.S. decimal characters.