Control.AccessibilityNotifyClients 方法

參考

定義

命名空間:: System.Windows.Forms

組件:: System.Windows.Forms.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

將 AccessibleEvents 告知協助工具用戶端應用程式。

多載

AccessibilityNotifyClients(AccessibleEvents, Int32)	將指定子控制項的指定 AccessibleEvents 告知協助工具用戶端應用程式。
AccessibilityNotifyClients(AccessibleEvents, Int32, Int32)	將指定子控制項的指定 AccessibleEvents 告知協助工具用戶端應用程式。

AccessibilityNotifyClients(AccessibleEvents, Int32)

將指定子控制項的指定 AccessibleEvents 告知協助工具用戶端應用程式。

protected:
 void AccessibilityNotifyClients(System::Windows::Forms::AccessibleEvents accEvent, int childID);

protected public:
 void AccessibilityNotifyClients(System::Windows::Forms::AccessibleEvents accEvent, int childID);

protected void AccessibilityNotifyClients (System.Windows.Forms.AccessibleEvents accEvent, int childID);

protected internal void AccessibilityNotifyClients (System.Windows.Forms.AccessibleEvents accEvent, int childID);

member this.AccessibilityNotifyClients : System.Windows.Forms.AccessibleEvents * int -> unit

Protected Sub AccessibilityNotifyClients (accEvent As AccessibleEvents, childID As Integer)

Protected Friend Sub AccessibilityNotifyClients (accEvent As AccessibleEvents, childID As Integer)

參數

accEvent: AccessibleEvents

要通知協助工具用戶端應用程式的 AccessibleEvents。

childID: Int32

要通知協助工具事件的子 Control。

範例

下列程式碼範例示範如何使用 AccessibleObject 和 Control.ControlAccessibleObject 類別來公開無障礙資訊，建立協助工具感知圖表控制項。控制項會繪製兩條曲線以及圖例。衍生 ChartControlAccessibleObject 自 ControlAccessibleObject 的類別用於方法中 CreateAccessibilityInstance ，以提供圖表控制項的自訂可存取訊號。由於圖表圖例不是實際的 Control 控制項，而是由圖表控制項繪製，因此它不會有任何內建的可存取訊號。因此，類別會 ChartControlAccessibleObjectGetChild 覆寫方法，以傳回 CurveLegendAccessibleObject ，代表圖例每個部分的可存取訊號。當可存取感知應用程式使用此控制項時，控制項可以提供必要的可存取訊號。

此程式碼摘錄示範如何呼叫 AccessibilityNotifyClients 方法。如需完整的程式碼範例， AccessibleObject 請參閱類別概觀。

   // Gets or sets the location for the curve legend.
   Point get()
   {
      return location;
   }

   void set( Point value )
   {
      location = value;
      chart->Invalidate();
      
      // Notifies the chart of the location change. This is used for
      // the accessibility information. AccessibleEvents::LocationChange
      // tells the chart the reason for the notification.
      chart->AccessibilityNotifyClients( AccessibleEvents::LocationChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
   }

}

property String^ Name 
{

   // Gets or sets the Name for the curve legend.
   String^ get()
   {
      return name;
   }

   void set( String^ value )
   {
      if ( name != value )
      {
         name = value;
         chart->Invalidate();
         
         // Notifies the chart of the name change. This is used for
         // the accessibility information. AccessibleEvents::NameChange
         // tells the chart the reason for the notification.
         chart->AccessibilityNotifyClients( AccessibleEvents::NameChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
      }
   }

}

property bool Selected 
{

   // Gets or sets the Selected state for the curve legend.
   bool get()
   {
      return selected;
   }

   void set( bool value )
   {
      if ( selected != value )
      {
         selected = value;
         chart->Invalidate();
         
         // Notifies the chart of the selection value change. This is used for
         // the accessibility information. The AccessibleEvents value depends upon
         // if the selection is true (AccessibleEvents::SelectionAdd) or
         // false (AccessibleEvents::SelectionRemove).
         chart->AccessibilityNotifyClients( selected ? AccessibleEvents::SelectionAdd : AccessibleEvents::SelectionRemove, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
      }
   }

    // Gets or sets the location for the curve legend.
    public Point Location
    {   
        get {
            return location;
        }
        set {
            location = value;
            chart.Invalidate();

            // Notifies the chart of the location change. This is used for
            // the accessibility information. AccessibleEvents.LocationChange
            // tells the chart the reason for the notification.

            chart.AccessibilityNotifyClients(AccessibleEvents.LocationChange, 
                ((CurveLegendAccessibleObject)AccessibilityObject).ID);
        }
    }            

    // Gets or sets the Name for the curve legend.
    public string Name
    {   
        get {
            return name;
        }
        set {
            if (name != value) 
            {
                name = value;
                chart.Invalidate();

                // Notifies the chart of the name change. This is used for
                // the accessibility information. AccessibleEvents.NameChange
                // tells the chart the reason for the notification.

                chart.AccessibilityNotifyClients(AccessibleEvents.NameChange, 
                    ((CurveLegendAccessibleObject)AccessibilityObject).ID);
            }
        }
    }

    // Gets or sets the Selected state for the curve legend.
    public bool Selected
    {   
        get {
            return selected;
        }
        set {
            if (selected != value) 
            {
                selected = value;
                chart.Invalidate();

                // Notifies the chart of the selection value change. This is used for
                // the accessibility information. The AccessibleEvents value depends upon
                // if the selection is true (AccessibleEvents.SelectionAdd) or 
                // false (AccessibleEvents.SelectionRemove).
                chart.AccessibilityNotifyClients(
                    selected ? AccessibleEvents.SelectionAdd : AccessibleEvents.SelectionRemove, 
                    ((CurveLegendAccessibleObject)AccessibilityObject).ID);
            }
        }
    }

' Gets or sets the location for the curve legend.            
Public Property Location() As Point
    Get
        Return m_location
    End Get
    Set
        m_location = value
        chart.Invalidate()

        ' Notifies the chart of the location change. This is used for
        ' the accessibility information. AccessibleEvents.LocationChange
        ' tells the chart the reason for the notification.
        chart.ExposeAccessibilityNotifyClients(AccessibleEvents.LocationChange, _
                CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
    End Set
End Property

' Gets or sets the Name for the curve legend.            
Public Property Name() As String
    Get
        Return m_name
    End Get
    Set
        If m_name <> value Then
            m_name = value
            chart.Invalidate()

            ' Notifies the chart of the name change. This is used for
            ' the accessibility information. AccessibleEvents.NameChange
            ' tells the chart the reason for the notification. 
            chart.ExposeAccessibilityNotifyClients(AccessibleEvents.NameChange, _
                    CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
        End If
    End Set
End Property

' Gets or sets the Selected state for the curve legend.            
Public Property Selected() As Boolean
    Get
        Return m_selected
    End Get
    Set
        If m_selected <> value Then
            m_selected = value
            chart.Invalidate()

            ' Notifies the chart of the selection value change. This is used for
            ' the accessibility information. The AccessibleEvents value varies
            ' on whether the selection is true (AccessibleEvents.SelectionAdd) or 
            ' false (AccessibleEvents.SelectionRemove). 
            If m_selected Then
                chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionAdd, _
                        CType(AccessibilityObject, CurveLegendAccessibleObject).ID) 
            Else
                chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionRemove, _
                        CType(AccessibilityObject, CurveLegendAccessibleObject).ID) 
            End If
        End If
    End Set
End Property

備註

您必須針對每個 AccessibleEvents 協助工具用戶端應用程式呼叫 Control.ControlAccessibleObject.NotifyClients 方法，才能收到通知。 NotifyClients當屬性設定或從事件處理常式內設定或從中時，通常會呼叫方法。例如，您可以呼叫方法， NotifyClients 並從事件的事件處理常式 Control.VisibleChanged 內傳入 AccessibleEvents 的值 Hide 。

另請參閱

適用於

AccessibilityNotifyClients(AccessibleEvents, Int32, Int32)