DragDrop Event

Control.DragDrop Event


Occurs when a drag-and-drop operation is completed.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public Event DragDrop As DragEventHandler

The X and Y properties of the DragEventArgs are in screen coordinates, not client coordinates. The following line of Visual C# code converts the properties to a client Point.

Point clientPoint = targetControl.PointToClient(new Point(de.X, de.Y));

In versions earlier than .NET Framework 2.0, if you put a UserControl with DragEnter and DragDrop events on a Windows Form and drag and drop something onto the UserControl at design time, the DropDrop and DropEnter events are raised. However, when you close and reopen the solution, the DragEnter and DragDrop events are not raised again.

For more information about handling events, see Handling and Raising Events.

This code excerpt demonstrates using the DragDrop event. See the DoDragDrop method for the complete code example.

Private Sub ListDragTarget_DragDrop(ByVal sender As Object, ByVal e As DragEventArgs) Handles ListDragTarget.DragDrop
    ' Ensures that the list item index is contained in the data.

    If (e.Data.GetDataPresent(GetType(System.String))) Then

        Dim item As Object = CType(e.Data.GetData(GetType(System.String)), System.Object)

        ' Perform drag-and-drop, depending upon the effect.
        If (e.Effect = DragDropEffects.Copy Or _
            e.Effect = DragDropEffects.Move) Then

            ' Insert the item.
            If (indexOfItemUnderMouseToDrop <> ListBox.NoMatches) Then
                ListDragTarget.Items.Insert(indexOfItemUnderMouseToDrop, item)

            End If
        End If
        ' Reset the label text.
        DropLocationLabel.Text = "None"
    End If
End Sub

.NET Framework
Available since 1.1
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