UnboundDataSource.ValueNeeded Event

Occurs before a value is pulled from the data source.

Namespace: DevExpress.Xpf.Core.DataSources

Assembly: DevExpress.Xpf.Core.v24.2.dll

NuGet Package: DevExpress.Wpf.Core

Declaration

C#

public event EventHandler<UnboundSourceValueNeededEventArgs> ValueNeeded

VB.NET

Public Event ValueNeeded As EventHandler(Of UnboundSourceValueNeededEventArgs)

Event Data

The ValueNeeded event's data class is UnboundSourceValueNeededEventArgs. The following properties provide information specific to this event:

Property	Description
PropertyIndex
PropertyName	Gets the name of the property whose value is requested.
RowIndex	Gets the row index of the value.
Tag	Gets an object that contains data associated with the value.
Value	Specifies the value which is requested.

The event data class exposes the following methods:

Method
SetValue<T>(T)

Remarks

Handle the ValueNeeded event to pull a value from the data source.

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the ValueNeeded event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

XAML

use-unbounddatasource-to-populate-wpf-data-grid-with-data/CS/UnboundSource/MainWindow.xaml#L20

Count="5"
ValueNeeded="UnboundDataSource_ValueNeeded"
ValuePushed="UnboundDataSource_ValuePushed">