DragDropBehaviorProperties.AllowDrop Property

Gets or sets whether users are allowed to drop data elements on the attached control.

Namespace: DevExpress.Utils.DragDrop

Assembly: DevExpress.Utils.v23.2.dll

NuGet Packages: DevExpress.Utils, DevExpress.Wpf.Core

Declaration

C#

[DefaultValue(true)]
[DXCategory("DragDrop")]
public bool AllowDrop { get; set; }

VB.NET

<DefaultValue(True)>
<DXCategory("DragDrop")>
Public Property AllowDrop As Boolean

Property Value

Type	Default	Description
Boolean	true	true to allow users to drop data elements on the attached control; otherwise, false.

Remarks

Set the AllowDrag property to false to use the attached control as the target of drag operations only.

To use the attached control as the source only, set the AllowDrop property to false. You can use the DragEnter event’s AllowDrop argument to override this setting for a particular control. You can also use the Cursor event argument to specify the mouse pointer that indicates whether it is allowed to drop items onto the control.

Example

This example shows how to prohibit to drop specific data.

C#

private void dragDropEvents1_DragEnter(object sender, DragEnterEventArgs e) {
    List<TreeListNode> list = e.Data as List<TreeListNode>;
    // You can prohibit to drop specific data.
    if (list.Find((x) => x.GetValue(colDEPARTMENT1).ToString().Contains("Finance")) != null) {
        e.AllowDrop = false;
        e.Cursor = Cursors.No;
        e.Handled = true;
    }
}

private void dragDropEvents1_DragOver(object sender, DevExpress.Utils.DragDrop.DragOverEventArgs e) {
    List<TreeListNode> list = e.Data as List<TreeListNode>;
    // You can prohibit to drop specific data.
    if (list.Find((x) => x.GetValue(colDEPARTMENT1).ToString().Contains("Finance")) != null) {
        e.Cursor = Cursors.No;
        e.Handled = true;
    }
}

VB.NET

Private Sub dragDropEvents1_DragEnter(ByVal sender As Object, ByVal e As DevExpress.Utils.DragDrop.DragEnterEventArgs) _
    Handles dragDropEvents1.DragEnter
    Dim list As List(Of TreeListNode) = TryCast(e.Data, List(Of TreeListNode))
    ' You can prohibit to drop specific data.
    If list.Find(Function(x) x.GetValue(colDEPARTMENT1).ToString().Contains("Finance")) IsNot Nothing Then
        e.AllowDrop = false
        e.Cursor = Cursors.No
        e.Handled = True
    End If
End Sub

Private Sub dragDropEvents1_DragOver(ByVal sender As Object, ByVal e As DevExpress.Utils.DragDrop.DragOverEventArgs) _
    Handles dragDropEvents1.DragOver
    Dim list As List(Of TreeListNode) = TryCast(e.Data, List(Of TreeListNode))
    ' You can prohibit to drop specific data.
    If list.Find(Function(x) x.GetValue(colDEPARTMENT1).ToString().Contains("Finance")) IsNot Nothing Then
        e.Cursor = Cursors.No
        e.Handled = True
    End If
End Sub

Note

Run the XtraTreeList or XtraGrid demo and click Open Solution for more examples.

Related GitHub Examples

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

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.

C#

drag-drop-grid-rows-to-treelist/CS/DragAndDropRows/Form1.cs#L54

behaviorManager1.Attach<DragDropBehavior>(gridView, behavior => {
    behavior.Properties.AllowDrop = false;
    behavior.Properties.InsertIndicatorVisible = true;

VB.NET

drag-drop-grid-rows-to-treelist/VB/DragAndDropRows/Form1.vb#L53

behaviorManager1.Attach(Of DragDropBehavior)(gridView, Sub(behavior)
    behavior.Properties.AllowDrop = False
    behavior.Properties.InsertIndicatorVisible = True