Статья
11/18/2011

ImageBrush Class

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

Paints an area with an image.

Inheritance Hierarchy

System.Object
  System.Windows.DependencyObject
    System.Windows.Media.Brush
      System.Windows.Media.TileBrush
        System.Windows.Media.ImageBrush

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

Syntax

'Declaration
Public NotInheritable Class ImageBrush _
    Inherits TileBrush

public sealed class ImageBrush : TileBrush

<ImageBrush .../>

The ImageBrush type exposes the following members.

Constructors

	Name	Description
	ImageBrush	Initializes a new instance of the ImageBrush class.

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Properties

	Name	Description
	AlignmentX	Gets or sets the horizontal alignment of content in the TileBrush base tile. (Inherited from TileBrush.)
	AlignmentY	Gets or sets the vertical alignment of content in the TileBrush base tile. (Inherited from TileBrush.)
	Dispatcher	Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
	ImageSource	Gets or sets the image displayed by this ImageBrush.
	Opacity	Gets or sets the degree of opacity of a Brush. (Inherited from Brush.)
	RelativeTransform	Gets or sets the transformation that is applied to the brush using relative coordinates. (Inherited from Brush.)
	Stretch	Gets or sets a value that specifies how the content of this TileBrush stretches to fit its tiles. (Inherited from TileBrush.)
	Transform	Gets or sets the transformation that is applied to the brush. (Inherited from Brush.)

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Methods

	Name	Description
	CheckAccess	Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
	ClearValue	Clears the local value of a dependency property. (Inherited from DependencyObject.)
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetAnimationBaseValue	Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	GetValue	Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ReadLocalValue	Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
	SetValue	Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Events

	Name	Description
	ImageFailed	Occurs when there is an error associated with image retrieval or format.
	ImageOpened	Occurs when the image source is downloaded and decoded with no failure. You can use this event to determine the size of an image before rendering it.

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Fields

	Name	Description
	ImageSourceProperty	Identifies the ImageSource dependency property.

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Remarks

An ImageBrush paints an area with an ImageSource. The ImageSource subclass that is defined by Silverlight 5 is BitmapImage, which describes a bitmap graphic.

An ImageBrush is a type of TileBrush that defines its content as an image. You can control how the image is stretched, aligned, and tiled, enabling you to produce patterns and other effects.

One use for an ImageBrush is to create a decorative effect for text in your application.

If the ImageSource property is set to an invalid format, or is specified to a URI that cannot be resolved, then the ImageFailed event is raised.

Examples

The following XAML example shows how to set the Foreground property of a TextBlock to an ImageBrush, whose image is used as the fill for the TextBlock rendered text.

<!-- TextBlock with an image brush applied to the text. -->
<TextBlock FontFamily="Verdana" FontSize="72"
 FontStyle="Italic" FontWeight="Bold">
    SHRUBBERY
  <TextBlock.Foreground>
    <ImageBrush ImageSource="forest.jpg"/>
  </TextBlock.Foreground>
</TextBlock>

The following illustration shows the results of this XAML example.

The output of the code

Output from an ImageBrush.

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.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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