wpf-devexpress-dot-xpf-dot-grid-dot-dataviewbase-c0a94fa1.md
Occurs continuously while a record is dragged (moved) within the drop target’s boundary.
Namespace : DevExpress.Xpf.Grid
Assembly : DevExpress.Xpf.Grid.v25.2.Core.dll
NuGet Package : DevExpress.Wpf.Grid.Core
public event EventHandler<DragRecordOverEventArgs> DragRecordOver
Public Event DragRecordOver As EventHandler(Of DragRecordOverEventArgs)
The DragRecordOver event's data class is DragRecordOverEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| AllowedEffects | Gets a member of the DragDropEffects enumeration that specifies which operations are allowed by the originator of the drag event. Inherited from DragEventArgsBase. |
| Data | Gets or sets a data object that contains the data associated with the corresponding drag event. Inherited from DragEventArgsBase. |
| DropPosition | Gets a drop position that specifies how a record is placed after it has been dropped. Inherited from DragEventArgsBase. |
| DropPositionRelativeCoefficient | Gets a number between 0 and 1, presenting a drop position relative to the target record. |
| Effects | Gets or sets the target drag-and-drop operation. Inherited from DragEventArgsBase. |
| Handled | Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route. Inherited from RoutedEventArgs. |
| IsFromOutside | Gets whether the dragged record is from another control. Inherited from DragEventArgsBase. |
| KeyStates | Gets a flag enumeration indicating the current state of the SHIFT, CTRL, and ALT keys, as well as the state of the mouse buttons. Inherited from DragEventArgsBase. |
| OriginalSource | Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs. |
| RoutedEvent | Gets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs. |
| Source | Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs. |
| TargetRecord | Gets a record that is drop target. Inherited from DragEventArgsBase. |
| TargetRowHandle | Gets the target row handle. Inherited from DragEventArgsBase. |
The event data class exposes the following methods:
| Method | Description |
|---|---|
| GetRecordType() | Gets the Type of the transferred records. Inherited from DragEventArgsBase. |
| InvokeEventHandler(Delegate, Object) | When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation. Inherited from RoutedEventArgs. |
| OnSetSource(Object) | When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes. Inherited from RoutedEventArgs. |
You can use the DragRecordOver event to deny a drop operation over specific records and specify visual feedback indicating the operation is not allowed:
<dxg:GridControl>
<!---->
<dxg:GridControl.View>
<dxg:TreeListView AllowDragDrop="True" DragRecordOver="OnDragRecordOver" />
</dxg:GridControl.View>
</dxg:GridControl>
void OnDragRecordOver(object sender, DragRecordOverEventArgs e) {
string position = ((Employee)e.TargetRecord).Position;
if (position == "President" || position == "Vice President") {
e.Effects = DragDropEffects.None;
e.Handled = true;
}
}
The following code snippets (auto-collected from DevExpress Examples) contain references to the DragRecordOver 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.
how-to-implement-drag-and-drop-between-gridcontrols-t566656/CS/MainWindow.xaml#L19
AllowDragDrop="True"
DragRecordOver="OnDragRecordOver"/>
</dxg:GridControl.View>
AllowDragDrop="True"
DragRecordOver="OnDragRecordOver"
DropRecord="OnDropRecord"/>
<dxg:GridControl.View>
<dxg:TableView AutoWidth="True" AllowDragDrop="True" DragRecordOver="OnDragRecordOver" />
</dxg:GridControl.View>
#line 19 "..\..\..\MainWindow.xaml"
((DevExpress.Xpf.Grid.TreeListView)(target)).DragRecordOver += new System.EventHandler<DevExpress.Xpf.Core.DragRecordOverEventArgs>(this.OnDragRecordOver);
#line 16 "..\..\..\MainWindow.xaml"
((DevExpress.Xpf.Grid.TableView)(target)).DragRecordOver += new System.EventHandler<DevExpress.Xpf.Core.DragRecordOverEventArgs>(this.OnDragRecordOver);
#ExternalSource("..\..\..\MainWindow.xaml",19)
AddHandler CType(target,DevExpress.Xpf.Grid.TreeListView).DragRecordOver, New System.EventHandler(Of DevExpress.Xpf.Core.DragRecordOverEventArgs)(AddressOf Me.OnDragRecordOver)
#ExternalSource("..\..\..\MainWindow.xaml",16)
AddHandler CType(target,DevExpress.Xpf.Grid.TableView).DragRecordOver, New System.EventHandler(Of DevExpress.Xpf.Core.DragRecordOverEventArgs)(AddressOf Me.OnDragRecordOver)
See Also