Control.DragDrop Control.DragDrop Control.DragDrop Control.DragDrop Event

定義

發生於拖放作業完成時。Occurs when a drag-and-drop operation is completed.

public:
 event System::Windows::Forms::DragEventHandler ^ DragDrop;
public event System.Windows.Forms.DragEventHandler DragDrop;
member this.DragDrop : System.Windows.Forms.DragEventHandler 
Public Custom Event DragDrop As DragEventHandler 

範例

此程式碼摘錄示範使用DragDrop事件。This code excerpt demonstrates using the DragDrop event. 請參閱DoDragDrop完整的程式碼範例中的方法。See the DoDragDrop method for the complete code example.

void ListDragTarget_DragDrop( Object^ /*sender*/, System::Windows::Forms::DragEventArgs^ e )
{
   // Ensure that the list item index is contained in the data.
   if ( e->Data->GetDataPresent( System::String::typeid ) )
   {
      Object^ item = dynamic_cast<Object^>(e->Data->GetData( System::String::typeid ));
      
      // Perform drag-and-drop, depending upon the effect.
      if ( e->Effect == DragDropEffects::Copy || e->Effect == DragDropEffects::Move )
      {
         // Insert the item.
         if ( indexOfItemUnderMouseToDrop != ListBox::NoMatches )
                        ListDragTarget->Items->Insert( indexOfItemUnderMouseToDrop, item );
         else
                        ListDragTarget->Items->Add( item );
      }
   }

   // Reset the label text.
   DropLocationLabel->Text = "None";
}
private void ListDragTarget_DragDrop(object sender, System.Windows.Forms.DragEventArgs e) 
{
    // Ensure that the list item index is contained in the data.
    if (e.Data.GetDataPresent(typeof(System.String))) {

        Object item = (object)e.Data.GetData(typeof(System.String));

        // Perform drag-and-drop, depending upon the effect.
        if (e.Effect == DragDropEffects.Copy ||
            e.Effect == DragDropEffects.Move) {
        
            // Insert the item.
            if (indexOfItemUnderMouseToDrop != ListBox.NoMatches)
                ListDragTarget.Items.Insert(indexOfItemUnderMouseToDrop, item);
            else
                ListDragTarget.Items.Add(item);
            
        }
    }
    // Reset the label text.
    DropLocationLabel.Text = "None";
}
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)
            Else
                ListDragTarget.Items.Add(item)

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

備註

XY屬性的DragEventArgs會以螢幕座標表示,工作區座標。The X and Y properties of the DragEventArgs are in screen coordinates, not client coordinates. Visual C# 程式碼的下一行會將屬性轉換為用戶端PointThe following line of Visual C# code converts the properties to a client Point.

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

注意

在版本早於.NET Framework 2.0.NET Framework 2.0,如果您將UserControlDragEnterDragDropWindows Form 上的事件並拖到的項目UserControl在設計階段,DropDropDropEnter事件引發。In versions earlier than .NET Framework 2.0.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. 不過,當您關閉並重新開啟方案,DragEnterDragDrop不會再次引發事件。However, when you close and reopen the solution, the DragEnter and DragDrop events are not raised again.

如需有關如何處理事件的詳細資訊,請參閱 < 處理和引發事件For more information about handling events, see Handling and Raising Events.

適用於

另請參閱