SPField.EnforceUniqueValues Property

Gets or sets a Boolean value that specifies whether to enforce uniqueness in column values. The default is false.

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

<ClientCallableAttribute> _
<ClientCallableConstraintAttribute(FixedId := "1", Type := ClientCallableConstraintType.Custom, Value := "The value can not be set to FALSE for the built-in fields or for the site columns")> _
Public Property EnforceUniqueValues As Boolean
Dim instance As SPField
Dim value As Boolean

value = instance.EnforceUniqueValues

instance.EnforceUniqueValues = value

Property Value

Type: System.Boolean
Returns true to enforce uniqueness in values that populate a specified column; otherwise false. The default is false.


You cannot set this property to true for a built-in field or for a site column.

When you set this property to true, you should also set the Indexed property to true.

The equivalent XML attribute for the Field element in a field definition is AllowDuplicateValues.