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Brush.Opacity Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets or sets the degree of opacity of a Brush.

Namespace:  System.Windows.Media
Assembly:  System.Windows (in System.Windows.dll)

Syntax

'Declaration
Public Property Opacity As Double
public double Opacity { get; set; }
<brush Opacity="double"/>

Property Value

Type: System.Double
The value of the Opacity property is expressed as a value between 0 and 1.0. The default value is 1.0.

Remarks

Dependency property identifier field: OpacityProperty

An Opacity value of 0 indicates that the brush is completely transparent, while a value of 1 indicates that the brush is completely opaque. A value of 0.5 indicates the brush is 50% opaque, a value of 0.725 indicates the brush is 72.5% opaque, and so on. Values less than 0 are treated as 0, while values greater than 1 are treated as 1.

The following illustrations shows a red rectangle with several different Opacity values.

Opacity = 1

Rectangle with 100 percent opacity.

Opacity = 0.7

Red rectangle.

Opacity = 0.5

Rectangle with 50 percent opacity.

Opacity = 0.2

Rectangle with 20 percent opacity.

Opacity = 0

Rectangle with 0% opacity.

An Opacity of 0 applied to any Brush is still hit testable. Only a true null Brush is not hit testable. You could however set IsHitTestVisible to false to remove any hit testing against the UIElement where the Brush is ultimately applied.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

See Also

Reference

Other Resources