DrawToolTipEventArgs.AssociatedControl 属性
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
获取要为其绘制 ToolTip 的控件。
public:
property System::Windows::Forms::Control ^ AssociatedControl { System::Windows::Forms::Control ^ get(); };public System.Windows.Forms.Control AssociatedControl { get; }public System.Windows.Forms.Control? AssociatedControl { get; }member this.AssociatedControl : System.Windows.Forms.ControlPublic ReadOnly Property AssociatedControl As Control属性值
发生 Control 事件时与 ToolTip 关联的 Draw。 如果工具提示未与控件关联，则返回值为 null。
示例
下面的代码示例演示如何自定义绘制 ToolTip。 该示例创建 ，并将其关联到 位于 上的Form三Button个ToolTip控件。 该示例将 OwnerDraw 属性设置为 true 并处理 Draw 事件。 在事件处理程序中 Draw ， ToolTip 根据 显示的按钮 ToolTip ，以不同的方式自定义绘制，如 属性所示 DrawToolTipEventArgs.AssociatedControl 。
下面的代码示例摘录演示了如何使用 AssociatedControl 属性。 有关完整的代码示例， DrawToolTipEventArgs 请参阅类概述。
// 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
注解
ToolTip由于 可以通过 方法与多个控件ToolTip.SetToolTip相关联，AssociatedControl因此 可以使用 属性来确定与事件关联的控件Draw。 如果要根据关联的控件执行不同的工具提示自定义，这非常有用。
