DragEventArgs.Y DragEventArgs.Y DragEventArgs.Y DragEventArgs.Y Property

定義

取得滑鼠指標的 Y 座標 (在螢幕座標中)。Gets the y-coordinate of the mouse pointer, in screen coordinates.

public:
 property int Y { int get(); };
public int Y { get; }
member this.Y : int
Public ReadOnly Property Y As Integer

屬性值

滑鼠指標的 Y 座標 (單位為像素)。The y-coordinate of the mouse pointer in pixels.

範例

下列範例示範兩個ListBox控制項之間的拖放作業。The following example demonstrates a drag-and-drop operation between two ListBox controls. 此範例會在DoDragDrop拖曳動作開始時呼叫方法。The example calls the DoDragDrop method when the drag action starts. 如果滑鼠在SystemInformation.DragSize MouseDown事件期間移動了滑鼠的位置, 則會開始拖曳動作。The drag action starts if the mouse has moved more than SystemInformation.DragSize from the mouse location during the MouseDown event. 方法是用來判斷MouseDown事件期間要拖曳的專案索引。 IndexFromPointThe IndexFromPoint method is used to determine the index of the item to drag during the MouseDown event.

此範例也會示範如何針對拖放作業使用自訂資料指標。The example also demonstrates using custom cursors for the drag-and-drop operation. 此範例假設應用程式目錄中有3dwarro.cur3dwno.cur個數據指標檔案, 分別用於自訂拖放和不放入游標。The example assumes that two cursor files, 3dwarro.cur and 3dwno.cur, exist in the application directory, for the custom drag and no-drop cursors, respectively. UseCustomCursorsCheck 如果CheckBox已核取, 則會使用自訂資料指標。The custom cursors will be used if the UseCustomCursorsCheckCheckBox is checked. 自訂資料指標是在GiveFeedback事件處理常式中設定。The custom cursors are set in the GiveFeedback event handler.

鍵盤狀態會在右側DragOver ListBox的事件處理常式中進行評估, 以根據 SHIFT、ctrl、ALT 或 CTRL + ALT 鍵的狀態來判斷拖曳作業的依據。The keyboard state is evaluated in the DragOver event handler for the right ListBox, to determine what the drag operation will be based upon state of the SHIFT, CTRL, ALT, or CTRL+ALT keys. 在中ListBox , 放置的位置也會在DragOver事件期間決定。The location in the ListBox where the drop would occur is also determined during the DragOver event. 如果要捨棄的資料不String是, DragEventArgs.Effect則會設定為DragDropEffects.NoneIf the data to drop is not a String, then the DragEventArgs.Effect is set to DragDropEffects.None. 最後, 放置的狀態會顯示在中DropLocationLabelLabelFinally, the status of the drop is displayed in the DropLocationLabelLabel.

ListBoxString ListBox在事件處理常式中決定要卸載的資料, 並將值加入至中的適當位置。 DragDropThe data to drop for the right ListBox is determined in the DragDrop event handler and the String value is added at the appropriate place in the ListBox. 如果拖曳作業移到表單的範圍外, 則會在QueryContinueDrag事件處理常式中取消拖放作業。If the drag operation moves outside the bounds of the form, then the drag-and-drop operation is canceled in the QueryContinueDrag event handler.

這段程式碼摘錄會DragEventArgs示範如何使用類別。This code excerpt demonstrates using the DragEventArgs class. 如需完整的程式碼範例, 請參閱方法。DoDragDropSee the DoDragDrop method for the complete code example.

void ListDragTarget_DragOver( Object^ /*sender*/, System::Windows::Forms::DragEventArgs^ e )
{
   // Determine whether string data exists in the drop data. If not, then
   // the drop effect reflects that the drop cannot occur.
   if (  !e->Data->GetDataPresent( System::String::typeid ) )
   {
      e->Effect = DragDropEffects::None;
      DropLocationLabel->Text = "None - no string data.";
      return;
   }

   // Set the effect based upon the KeyState.
   if ( (e->KeyState & (8 + 32)) == (8 + 32) && ((e->AllowedEffect & DragDropEffects::Link) == DragDropEffects::Link) )
   {
      // KeyState 8 + 32 = CTL + ALT
      // Link drag-and-drop effect.
      e->Effect = DragDropEffects::Link;
   }
   else
   if ( (e->KeyState & 32) == 32 && ((e->AllowedEffect & DragDropEffects::Link) == DragDropEffects::Link) )
   {
      // ALT KeyState for link.
      e->Effect = DragDropEffects::Link;
   }
   else
   if ( (e->KeyState & 4) == 4 && ((e->AllowedEffect & DragDropEffects::Move) == DragDropEffects::Move) )
   {
      // SHIFT KeyState for move.
      e->Effect = DragDropEffects::Move;
   }
   else
   if ( (e->KeyState & 8) == 8 && ((e->AllowedEffect & DragDropEffects::Copy) == DragDropEffects::Copy) )
   {
      // CTL KeyState for copy.
      e->Effect = DragDropEffects::Copy;
   }
   else
   if ( (e->AllowedEffect & DragDropEffects::Move) == DragDropEffects::Move )
   {
      // By default, the drop action should be move, if allowed.
      e->Effect = DragDropEffects::Move;
   }
   else
            e->Effect = DragDropEffects::None;





   
   // Get the index of the item the mouse is below.
   // The mouse locations are relative to the screen, so they must be
   // converted to client coordinates.
   indexOfItemUnderMouseToDrop = ListDragTarget->IndexFromPoint( ListDragTarget->PointToClient( Point(e->X,e->Y) ) );
   
   // Updates the label text.
   if ( indexOfItemUnderMouseToDrop != ListBox::NoMatches )
   {
      DropLocationLabel->Text = String::Concat( "Drops before item # ", (indexOfItemUnderMouseToDrop + 1) );
   }
   else
            DropLocationLabel->Text = "Drops at the end.";
}
private void ListDragTarget_DragOver(object sender, System.Windows.Forms.DragEventArgs e) 
{

    // Determine whether string data exists in the drop data. If not, then
    // the drop effect reflects that the drop cannot occur.
    if (!e.Data.GetDataPresent(typeof(System.String))) {

        e.Effect = DragDropEffects.None;
        DropLocationLabel.Text = "None - no string data.";
        return;
    }

    // Set the effect based upon the KeyState.
    if ((e.KeyState & (8+32)) == (8+32) && 
        (e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link) {
        // KeyState 8 + 32 = CTL + ALT

        // Link drag-and-drop effect.
        e.Effect = DragDropEffects.Link;

    } else if ((e.KeyState & 32) == 32 && 
        (e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link) {

        // ALT KeyState for link.
        e.Effect = DragDropEffects.Link;

    } else if ((e.KeyState & 4) == 4 && 
        (e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move) {

        // SHIFT KeyState for move.
        e.Effect = DragDropEffects.Move;

    } else if ((e.KeyState & 8) == 8 && 
        (e.AllowedEffect & DragDropEffects.Copy) == DragDropEffects.Copy) {

        // CTL KeyState for copy.
        e.Effect = DragDropEffects.Copy;

    } else if ((e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move)  {

        // By default, the drop action should be move, if allowed.
        e.Effect = DragDropEffects.Move;

    } else
        e.Effect = DragDropEffects.None;
        
    // Get the index of the item the mouse is below. 

    // The mouse locations are relative to the screen, so they must be 
    // converted to client coordinates.

    indexOfItemUnderMouseToDrop = 
        ListDragTarget.IndexFromPoint(ListDragTarget.PointToClient(new Point(e.X, e.Y)));

    // Updates the label text.
    if (indexOfItemUnderMouseToDrop != ListBox.NoMatches){

        DropLocationLabel.Text = "Drops before item #" + (indexOfItemUnderMouseToDrop + 1);
    } else
        DropLocationLabel.Text = "Drops at the end.";

}
Private Sub ListDragTarget_DragOver(ByVal sender As Object, ByVal e As DragEventArgs) Handles ListDragTarget.DragOver
    ' Determine whether string data exists in the drop data. If not, then
    ' the drop effect reflects that the drop cannot occur.
    If Not (e.Data.GetDataPresent(GetType(System.String))) Then

        e.Effect = DragDropEffects.None
        DropLocationLabel.Text = "None - no string data."
        Return
    End If

    ' Set the effect based upon the KeyState.
    If ((e.KeyState And (8 + 32)) = (8 + 32) And _
        (e.AllowedEffect And DragDropEffects.Link) = DragDropEffects.Link) Then
        ' KeyState 8 + 32 = CTL + ALT

        ' Link drag-and-drop effect.
        e.Effect = DragDropEffects.Link

    ElseIf ((e.KeyState And 32) = 32 And _
        (e.AllowedEffect And DragDropEffects.Link) = DragDropEffects.Link) Then

        ' ALT KeyState for link.
        e.Effect = DragDropEffects.Link

    ElseIf ((e.KeyState And 4) = 4 And _
        (e.AllowedEffect And DragDropEffects.Move) = DragDropEffects.Move) Then

        ' SHIFT KeyState for move.
        e.Effect = DragDropEffects.Move

    ElseIf ((e.KeyState And 8) = 8 And _
        (e.AllowedEffect And DragDropEffects.Copy) = DragDropEffects.Copy) Then

        ' CTL KeyState for copy.
        e.Effect = DragDropEffects.Copy

    ElseIf ((e.AllowedEffect And DragDropEffects.Move) = DragDropEffects.Move) Then

        ' By default, the drop action should be move, if allowed.
        e.Effect = DragDropEffects.Move

    Else
        e.Effect = DragDropEffects.None
    End If

    ' Gets the index of the item the mouse is below. 

    ' The mouse locations are relative to the screen, so they must be 
    ' converted to client coordinates.

    indexOfItemUnderMouseToDrop = _
        ListDragTarget.IndexFromPoint(ListDragTarget.PointToClient(New Point(e.X, e.Y)))

    ' Updates the label text.
    If (indexOfItemUnderMouseToDrop <> ListBox.NoMatches) Then

        DropLocationLabel.Text = "Drops before item #" & (indexOfItemUnderMouseToDrop + 1)
    Else
        DropLocationLabel.Text = "Drops at the end."
    End If

End Sub

適用於

另請參閱