Form.Opacity 属性

定义

获取或设置窗体的不透明度级别。Gets or sets the opacity level of the form.

public:
 property double Opacity { double get(); void set(double value); };
[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.OpacityConverter))]
public double Opacity { get; set; }
member this.Opacity : double with get, set
Public Property Opacity As Double

属性值

窗体的不透明度级别。The level of opacity for the form. 默认值为 1.00。The default is 1.00.

属性

示例

下面的示例演示如何创建一个窗体,该窗体的不透明度级别为75%。The following example demonstrates how to create a form that is displayed with an opacity level of 75 percent. 它将创建一个新窗体,该窗体位于屏幕的中心,其 Opacity 属性集用于更改窗体的不透明度级别。It creates a new form that is positioned in the center of the screen with an Opacity property set to change the opacity level of the form. 该示例还将 Size 属性设置为提供的窗体大小大于窗体的默认大小。The example also sets the Size property to provide a larger sized form than the default size of the form.

此示例假设从事件处理程序或其他方法中的另一个窗体调用 CreateMyOpaqueForm 方法。This example assumes that the CreateMyOpaqueForm method is called from another form in an event handler or other method.

private:
   void CreateMyOpaqueForm()
   {
      // Create a new form.
      Form^ form2 = gcnew Form;

      // Set the text displayed in the caption.
      form2->Text = "My Form";

      // Set the opacity to 75%.
      form2->Opacity = .75;

      // Size the form to be 300 pixels in height and width.
      form2->Size = System::Drawing::Size( 300, 300 );

      // Display the form in the center of the screen.
      form2->StartPosition = FormStartPosition::CenterScreen;

      // Display the form as a modal dialog box.
      form2->ShowDialog();
   }
private void CreateMyOpaqueForm()
{
   // Create a new form.
   Form form2 = new Form();
   // Set the text displayed in the caption.
   form2.Text = "My Form";
   // Set the opacity to 75%.
   form2.Opacity = .75;
   // Size the form to be 300 pixels in height and width.
   form2.Size = new Size(300,300);
   // Display the form in the center of the screen.
   form2.StartPosition = FormStartPosition.CenterScreen;

   // Display the form as a modal dialog box.
   form2.ShowDialog();
}
Private Sub CreateMyOpaqueForm()
   ' Create a new form.
   Dim form2 As New Form()
   ' Set the text displayed in the caption.
   form2.Text = "My Form"
   ' Set the opacity to 75%.
   form2.Opacity = 0.75
   ' Size the form to be 300 pixels in height and width.
   form2.Size = New Size(300, 300)
   ' Display the form in the center of the screen.
   form2.StartPosition = FormStartPosition.CenterScreen

   ' Display the form as a modal dialog box.
   form2.ShowDialog()
End Sub

注解

使用 Opacity 属性可以指定窗体及其控件的透明度级别。The Opacity property enables you to specify a level of transparency for the form and its controls. 如果将此属性设置为小于100% (1.00)的值,则整个窗体(包括边框)将变得更加透明。When this property is set to a value less than 100 percent (1.00), the entire form, including borders, is made more transparent. 如果将此属性的值设置为0% (0.00),则会使窗体完全不可见。Setting this property to a value of 0 percent (0.00) makes the form completely invisible. 您可以使用此属性来提供不同的透明度级别,或提供各种效果,如逐步取消窗体在视图中的显示方式。You can use this property to provide different levels of transparency or to provide effects such as phasing a form in or out of view. 例如,你可以通过将 Opacity 属性设置为0% (0.00)的值并逐渐增加该值,直到达到100% (1.00)。For example, you can phase a form into view by setting the Opacity property to a value of 0 percent (0.00) and gradually increasing the value until it reaches 100 percent (1.00).

OpacityTransparencyKey 提供的透明度不同,仅当窗体及其控件的颜色与 TransparencyKey 属性中指定的值相同时,它才会使窗体及其控件完全透明。Opacity differs from the transparency provided by TransparencyKey, which only makes a form and its controls completely transparent if they are the same color as the value specified in the TransparencyKey property.

trueRightToLeftLayout 时,此属性不受支持。This property is not supported when RightToLeftLayout is true.

Opacity 属性取决于分层 Windows API。The Opacity property depends on the Layered Windows API. 有关详细信息,请参阅分层窗口For more information, see Layered Windows.

适用于

另请参阅