SPList.ValidationFormula Property

Gets or sets a formula that is evaluated each time that a list item is added or updated.

Namespace:  Microsoft.SharePoint
Assembly:  Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: Yes
Available in SharePoint Online

[ClientCallableConstraintAttribute(Type = ClientCallableConstraintType.NotNull, Sequence = )]
[ClientCallableConstraintAttribute(Type = ClientCallableConstraintType.MaxLength, Value = , Sequence = )]
[ClientCallablePropertyAttribute(ExcludeFromDefaultRetrieve = true)]
public string ValidationFormula { get; set; }

Property Value

Type: System.String
The formula that will be used to evaluate data in the item. The rules for constructing a formula are similar to those for creating formulas for calculated fields. For more information, see Calculated Field Formulas.


The string is too long. The maximum length of a validation formula string is 1024.

Each time that a list item is added or updated, the validation formula is evaluated. If the formula evaluates to false, or if a calculation error occurs, the update is not permitted and the message in the ValidationMessage property is displayed.

Keep in mind that each field in a list item has a ValidationFormula property of its own. The difference is that the validation formula for a field can refer only to that field, whereas the validation formula for a list item can refer to several or even all fields in the item.


Formula validation is independent of the type of validation controlled by the EnforceDataValidation property.