StatusBar.OnDrawItem(StatusBarDrawItemEventArgs) 方法

定義

命名空間:

System.Windows.Forms

組件:

System.Windows.Forms.dll

引發 OnDrawItem(StatusBarDrawItemEventArgs) 事件。

protected:
 virtual void OnDrawItem(System::Windows::Forms::StatusBarDrawItemEventArgs ^ sbdievent);

protected virtual void OnDrawItem (System.Windows.Forms.StatusBarDrawItemEventArgs sbdievent);

abstract member OnDrawItem : System.Windows.Forms.StatusBarDrawItemEventArgs -> unit
override this.OnDrawItem : System.Windows.Forms.StatusBarDrawItemEventArgs -> unit

Protected Overridable Sub OnDrawItem (sbdievent As StatusBarDrawItemEventArgs)

參數

sbdievent

StatusBarDrawItemEventArgs

StatusBarDrawItemEventArgs，其中包含事件資料。

範例

下列程式碼範例示範如何建立擁有者繪製 StatusBarPanel ，以顯示自訂背景和目前日期。 此範例會要求您已將 DrawItem 控制項的 StatusBar 事件連接到範例中所定義的事件處理常式。

private:
   void DrawMyPanel( Object^ /*sender*/, System::Windows::Forms::StatusBarDrawItemEventArgs^ sbdevent )
   {
      // Create a StringFormat object to align text in the panel.
      StringFormat^ sf = gcnew StringFormat;

      // Format the String of the StatusBarPanel to be centered.
      sf->Alignment = StringAlignment::Center;
      sf->LineAlignment = StringAlignment::Center;

      // Draw a back blackground in owner-drawn panel.
      sbdevent->Graphics->FillRectangle( Brushes::Black, sbdevent->Bounds );

      // Draw the current date (short date format) with white text in the control's font.
      sbdevent->Graphics->DrawString( DateTime::Today.ToShortDateString(), statusBar1->Font, Brushes::White, sbdevent->Bounds, sf );
   }

private void DrawMyPanel(object sender, System.Windows.Forms.StatusBarDrawItemEventArgs sbdevent)
{
   // Create a StringFormat object to align text in the panel.
   StringFormat sf = new StringFormat();
   // Format the String of the StatusBarPanel to be centered.
   sf.Alignment = StringAlignment.Center;
   sf.LineAlignment = StringAlignment.Center;

   // Draw a black background in owner-drawn panel.
   sbdevent.Graphics.FillRectangle(Brushes.Black, sbdevent.Bounds);
   // Draw the current date (short date format) with white text in the control's font.
   sbdevent.Graphics.DrawString(DateTime.Today.ToShortDateString(), 
      statusBar1.Font,Brushes.White,sbdevent.Bounds,sf);
}

Private Sub StatusBar1_DrawItem(ByVal sender As Object, ByVal sbdevent As System.Windows.Forms.StatusBarDrawItemEventArgs) Handles StatusBar1.DrawItem

   ' Create a StringFormat object to align text in the panel.
   Dim sf As New StringFormat()
   ' Format the String of the StatusBarPanel to be centered.
   sf.Alignment = StringAlignment.Center
   sf.LineAlignment = StringAlignment.Center

   ' Draw a black background in owner-drawn panel.
   sbdevent.Graphics.FillRectangle(Brushes.Black, sbdevent.Bounds)
   ' Draw the current date (short date format) with white text in the control's font.
   sbdevent.Graphics.DrawString(DateTime.Today.ToShortDateString(), StatusBar1.Font, Brushes.White, _
         New RectangleF(sbdevent.Bounds.X, sbdevent.Bounds.Y, _
         sbdevent.Bounds.Width, sbdevent.Bounds.Height), sf)
End Sub

備註

引發事件會透過委派叫用此事件處理常式。 如需詳細資訊，請參閱 處理和引發事件。

OnDrawItem 方法也允許衍生類別處理事件，而不用附加委派。 這是在衍生類別中處理事件的慣用技巧。

給繼承者的注意事項

當在衍生類別中覆寫 OnDrawItem(StatusBarDrawItemEventArgs) 時，請確定呼叫基底類別的 OnDrawItem(StatusBarDrawItemEventArgs) 方法，使已註冊的委派能接收到事件。

另請參閱

• DrawItem
• StatusBarDrawItemEventArgs