QueryContinueDragEventArgs Classe

Definição

public ref class QueryContinueDragEventArgs : EventArgs

[System.Runtime.InteropServices.ComVisible(true)]
public class QueryContinueDragEventArgs : EventArgs

[<System.Runtime.InteropServices.ComVisible(true)>]
type QueryContinueDragEventArgs = class
    inherit EventArgs

Public Class QueryContinueDragEventArgs
Inherits EventArgs

Herança

Object

EventArgs

QueryContinueDragEventArgs

Atributos

ComVisibleAttribute

Exemplos

Este excerto de código demonstra o uso da QueryContinueDragEventArgs classe com o QueryContinueDrag evento. Veja o DoDragDrop método para o exemplo completo do código.

void ListDragSource_QueryContinueDrag( Object^ sender, System::Windows::Forms::QueryContinueDragEventArgs^ e )
{
   // Cancel the drag if the mouse moves off the form.
   ListBox^ lb = dynamic_cast<ListBox^>(sender);
   if ( lb != nullptr )
   {
      Form^ f = lb->FindForm();

      // Cancel the drag if the mouse moves off the form. The screenOffset
      // takes into account any desktop bands that may be at the top or left
      // side of the screen.
      if ( ((Control::MousePosition.X - screenOffset.X) < f->DesktopBounds.Left) || ((Control::MousePosition.X - screenOffset.X) > f->DesktopBounds.Right) || ((Control::MousePosition.Y - screenOffset.Y) < f->DesktopBounds.Top) || ((Control::MousePosition.Y - screenOffset.Y) > f->DesktopBounds.Bottom) )
      {
         e->Action = DragAction::Cancel;
      }
   }
}

private void ListDragSource_QueryContinueDrag(object sender, QueryContinueDragEventArgs e)
{
    // Cancel the drag if the mouse moves off the form.
    ListBox lb = sender as ListBox;

    if (lb != null)
    {
        Form f = lb.FindForm();

        // Cancel the drag if the mouse moves off the form. The screenOffset
        // takes into account any desktop bands that may be at the top or left
        // side of the screen.
        if (((Control.MousePosition.X - screenOffset.X) < f.DesktopBounds.Left) ||
            ((Control.MousePosition.X - screenOffset.X) > f.DesktopBounds.Right) ||
            ((Control.MousePosition.Y - screenOffset.Y) < f.DesktopBounds.Top) ||
            ((Control.MousePosition.Y - screenOffset.Y) > f.DesktopBounds.Bottom))
        {
            e.Action = DragAction.Cancel;
        }
    }
}

Private Sub ListDragSource_QueryContinueDrag(ByVal sender As Object, ByVal e As QueryContinueDragEventArgs) Handles ListDragSource.QueryContinueDrag
    ' Cancel the drag if the mouse moves off the form.
    Dim lb As ListBox = CType(sender, ListBox)

    If (lb IsNot Nothing) Then

        Dim f As Form = lb.FindForm()

        ' Cancel the drag if the mouse moves off the form. The screenOffset
        ' takes into account any desktop bands that may be at the top or left
        ' side of the screen.
        If (((Control.MousePosition.X - screenOffset.X) < f.DesktopBounds.Left) Or
            ((Control.MousePosition.X - screenOffset.X) > f.DesktopBounds.Right) Or
            ((Control.MousePosition.Y - screenOffset.Y) < f.DesktopBounds.Top) Or
            ((Control.MousePosition.Y - screenOffset.Y) > f.DesktopBounds.Bottom)) Then

            e.Action = DragAction.Cancel
        End If
    End If
End Sub

Observações

O QueryContinueDrag evento ocorre durante uma operação de arrastar e largar e permite à fonte de arrastar determinar se a operação de arrastar e largar deve ser cancelada. A QueryContinueDragEventArgs especifica se e como deve proceder a operação de arrastar e largar, se alguma tecla modificadora é pressionada e se o utilizador pressionou a tecla ESC.

Por defeito, o QueryContinueDrag evento define Action para DragAction.Cancel se a tecla ESC for pressionada e para ActionDragAction.Drop se o botão esquerdo, do meio ou direito do rato for pressionado.

Para informações sobre o modelo de eventos, consulte Gestão e Angariação de Eventos.

Ver também

• DragAction
• DoDragDrop(Object, DragDropEffects)