DrawToolTipEventArgs.AssociatedControl 屬性

定義

取得 ToolTip 是針對哪一個控制項所繪製。Gets the control for which the ToolTip is being drawn.

public:
 property System::Windows::Forms::Control ^ AssociatedControl { System::Windows::Forms::Control ^ get(); };
public System.Windows.Forms.Control AssociatedControl { get; }
member this.AssociatedControl : System.Windows.Forms.Control
Public ReadOnly Property AssociatedControl As Control

屬性值

Control

發生 Control 事件時,與 ToolTip 關聯的 DrawThe Control that is associated with the ToolTip when the Draw event occurs. 如果工具提示沒有與任何控制項相關聯,此傳回值將為 nullThe return value will be null if the ToolTip is not associated with a control.

範例

下列程式碼範例示範如何自訂繪製 ToolTipThe following code example demonstrates how to custom draw the ToolTip. 此範例會建立 ToolTip ,並將它與 Button 位於上的三個控制項產生關聯 FormThe example creates a ToolTip and associates it to three Button controls located on the Form. 此範例會將 OwnerDraw 屬性設定為 true ,並處理 Draw 事件。The example sets the OwnerDraw property to true and handles the Draw event. Draw 事件處理常式中, ToolTip 會根據所顯示的按鈕 ToolTip (如屬性所示),以不同的方式繪製自訂繪製 DrawToolTipEventArgs.AssociatedControlIn the Draw event handler, the ToolTip is custom drawn differently depending on what button the ToolTip is being displayed for as indicated by the DrawToolTipEventArgs.AssociatedControl property.

下列程式碼範例摘錄示範如何使用 AssociatedControl 屬性。The following code example excerpt demonstrates how to use the AssociatedControl property. 如需 DrawToolTipEventArgs 完整的程式碼範例,請參閱類別總覽。See the DrawToolTipEventArgs class overview for the complete code example.

   // Handles drawing the ToolTip.
private:
   void toolTip1_Draw( System::Object^ /*sender*/, System::Windows::Forms::DrawToolTipEventArgs^ e )
   {
      // Draw the ToolTip differently depending on which 
      // control this ToolTip is for.
      // Draw a custom 3D border if the ToolTip is for button1.
      if ( e->AssociatedControl == button1 )
      {
         // Draw the standard background.
         e->DrawBackground();
         
         // Draw the custom border to appear 3-dimensional.
         array<Point>^ temp1 = {Point(0,e->Bounds.Height - 1),Point(0,0),Point(e->Bounds.Width - 1,0)};
         e->Graphics->DrawLines( SystemPens::ControlLightLight, temp1 );
         array<Point>^ temp2 = {Point(0,e->Bounds.Height - 1),Point(e->Bounds.Width - 1,e->Bounds.Height - 1),Point(e->Bounds.Width - 1,0)};
         e->Graphics->DrawLines( SystemPens::ControlDarkDark, temp2 );
         
         // Specify custom text formatting flags.
         TextFormatFlags sf = static_cast<TextFormatFlags>(TextFormatFlags::VerticalCenter | TextFormatFlags::HorizontalCenter | TextFormatFlags::NoFullWidthCharacterBreak);
         
         // Draw the standard text with customized formatting options.
         e->DrawText( sf );
      }
      // Draw a custom background and text if the ToolTip is for button2.
      else
      
      // Draw a custom background and text if the ToolTip is for button2.
      if ( e->AssociatedControl == button2 )
      {
         // Draw the custom background.
         e->Graphics->FillRectangle( SystemBrushes::ActiveCaption, e->Bounds );
         
         // Draw the standard border.
         e->DrawBorder();
         
         // Draw the custom text.
         // The using block will dispose the StringFormat automatically.
         StringFormat^ sf = gcnew StringFormat;
         try
         {
            sf->Alignment = StringAlignment::Center;
            sf->LineAlignment = StringAlignment::Center;
            sf->HotkeyPrefix = System::Drawing::Text::HotkeyPrefix::None;
            sf->FormatFlags = StringFormatFlags::NoWrap;
            System::Drawing::Font^ f = gcnew System::Drawing::Font( "Tahoma",9 );
            try
            {
               e->Graphics->DrawString( e->ToolTipText, f, SystemBrushes::ActiveCaptionText, e->Bounds, sf );
            }
            finally
            {
               if ( f )
                  delete safe_cast<IDisposable^>(f);
            }

         }
         finally
         {
            if ( sf )
               delete safe_cast<IDisposable^>(sf);
         }
      }
      // Draw the ToolTip using default values if the ToolTip is for button3.
      else if ( e->AssociatedControl == button3 )
      {
         e->DrawBackground();
         e->DrawBorder();
         e->DrawText();
      }
   }
// Handles drawing the ToolTip.
private void toolTip1_Draw(System.Object sender, 
    System.Windows.Forms.DrawToolTipEventArgs e)
{
    // Draw the ToolTip differently depending on which 
    // control this ToolTip is for.
    // Draw a custom 3D border if the ToolTip is for button1.
    if (e.AssociatedControl == button1)
    {
        // Draw the standard background.
        e.DrawBackground();

        // Draw the custom border to appear 3-dimensional.
        e.Graphics.DrawLines(SystemPens.ControlLightLight, new Point[] {
            new Point (0, e.Bounds.Height - 1), 
            new Point (0, 0), 
            new Point (e.Bounds.Width - 1, 0)
        });
        e.Graphics.DrawLines(SystemPens.ControlDarkDark, new Point[] {
            new Point (0, e.Bounds.Height - 1), 
            new Point (e.Bounds.Width - 1, e.Bounds.Height - 1), 
            new Point (e.Bounds.Width - 1, 0)
        });

        // Specify custom text formatting flags.
        TextFormatFlags sf = TextFormatFlags.VerticalCenter |
                             TextFormatFlags.HorizontalCenter |
                             TextFormatFlags.NoFullWidthCharacterBreak;

        // Draw the standard text with customized formatting options.
        e.DrawText(sf);
    }
    // Draw a custom background and text if the ToolTip is for button2.
    else if (e.AssociatedControl == button2)
    {
        // Draw the custom background.
        e.Graphics.FillRectangle(SystemBrushes.ActiveCaption, e.Bounds);

        // Draw the standard border.
        e.DrawBorder();

        // Draw the custom text.
        // The using block will dispose the StringFormat automatically.
        using (StringFormat sf = new StringFormat())
        {
            sf.Alignment = StringAlignment.Center;
            sf.LineAlignment = StringAlignment.Center;
            sf.HotkeyPrefix = System.Drawing.Text.HotkeyPrefix.None;
            sf.FormatFlags = StringFormatFlags.NoWrap;
            using (Font f = new Font("Tahoma", 9))
            {
                e.Graphics.DrawString(e.ToolTipText, f, 
                    SystemBrushes.ActiveCaptionText, e.Bounds, sf);
            }
        }
    }
    // Draw the ToolTip using default values if the ToolTip is for button3.
    else if (e.AssociatedControl == button3)
    {
        e.DrawBackground();
        e.DrawBorder();
        e.DrawText();
    }
}
' Handles drawing the ToolTip.
Private Sub toolTip1_Draw(ByVal sender As System.Object, _
    ByVal e As DrawToolTipEventArgs) Handles toolTip1.Draw
    ' Draw the ToolTip differently depending on which 
    ' control this ToolTip is for.

    ' Draw a custom 3D border if the ToolTip is for button1.
    If (e.AssociatedControl Is button1) Then
        ' Draw the standard background.
        e.DrawBackground()

        ' Draw the custom border to appear 3-dimensional.
        e.Graphics.DrawLines( _
            SystemPens.ControlLightLight, New Point() { _
            New Point(0, e.Bounds.Height - 1), _
            New Point(0, 0), _
            New Point(e.Bounds.Width - 1, 0)})
        e.Graphics.DrawLines( _
            SystemPens.ControlDarkDark, New Point() { _
            New Point(0, e.Bounds.Height - 1), _
            New Point(e.Bounds.Width - 1, e.Bounds.Height - 1), _
            New Point(e.Bounds.Width - 1, 0)})

        ' Specify custom text formatting flags.
        Dim sf As TextFormatFlags = TextFormatFlags.VerticalCenter Or _
                             TextFormatFlags.HorizontalCenter Or _
                             TextFormatFlags.NoFullWidthCharacterBreak

        ' Draw standard text with customized formatting options.
        e.DrawText(sf)
    ElseIf (e.AssociatedControl Is button2) Then
        ' Draw a custom background and text if the ToolTip is for button2.

        ' Draw the custom background.
        e.Graphics.FillRectangle(SystemBrushes.ActiveCaption, e.Bounds)

        ' Draw the standard border.
        e.DrawBorder()

        ' Draw the custom text.
        Dim sf As StringFormat = New StringFormat
        Try
            sf.Alignment = StringAlignment.Center
            sf.LineAlignment = StringAlignment.Center
            sf.HotkeyPrefix = System.Drawing.Text.HotkeyPrefix.None
            sf.FormatFlags = StringFormatFlags.NoWrap

            Dim f As Font = New Font("Tahoma", 9)
            Try
                e.Graphics.DrawString(e.ToolTipText, f, _
                    SystemBrushes.ActiveCaptionText, _
                    RectangleF.op_Implicit(e.Bounds), sf)
            Finally
                f.Dispose()
            End Try
        Finally
            sf.Dispose()
        End Try
    ElseIf (e.AssociatedControl Is button3) Then
        ' Draw the ToolTip using default values if the ToolTip is for button3.
        e.DrawBackground()
        e.DrawBorder()
        e.DrawText()
    End If
End Sub

備註

由於 ToolTip 可透過方法與多個控制項相關聯 ToolTip.SetToolTip ,因此 AssociatedControl 可以使用屬性來判斷事件所關聯的控制項 DrawBecause the ToolTip can be associated with multiple controls through the ToolTip.SetToolTip method, the AssociatedControl property can be used to determine which control the Draw event is associated with. 如果您想要根據相關聯的控制項執行不同的工具提示自訂,這會很有説明。This is helpful if you want to perform different ToolTip customization based on the associated control.

適用於

另請參閱