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BitmapImage Class

Definition

Provides a specialized BitmapSource that is optimized for loading images using Extensible Application Markup Language (XAML).

public ref class BitmapImage sealed : System::Windows::Media::Imaging::BitmapSource, System::ComponentModel::ISupportInitialize, System::Windows::Markup::IUriContext
public sealed class BitmapImage : System.Windows.Media.Imaging.BitmapSource, System.ComponentModel.ISupportInitialize, System.Windows.Markup.IUriContext
type BitmapImage = class
    inherit BitmapSource
    interface ISupportInitialize
    interface IUriContext
Public NotInheritable Class BitmapImage
Inherits BitmapSource
Implements ISupportInitialize, IUriContext
Inheritance
Implements

Examples

The following code examples demonstrate how to use a BitmapImage in Extensible Application Markup Language (XAML) and code.

<!-- Property Tag XAML Syntax -->
<Image Width="200"  Margin="5" Grid.Column="1" Grid.Row="1" >
   <Image.Source>
      <BitmapImage UriSource="sampleImages/bananas.jpg" />
   </Image.Source>
</Image>
<!-- Property Tag XAML Syntax -->
<Image Width="200"  Margin="5" Grid.Column="1" Grid.Row="1" >
   <Image.Source>
      <BitmapImage UriSource="sampleImages/bananas.jpg" />
   </Image.Source>
</Image>
// Create the image element.
Image simpleImage = new Image();    
simpleImage.Width = 200;
simpleImage.Margin = new Thickness(5);

// Create source.
BitmapImage bi = new BitmapImage();
// BitmapImage.UriSource must be in a BeginInit/EndInit block.
bi.BeginInit();
bi.UriSource = new Uri(@"/sampleImages/cherries_larger.jpg",UriKind.RelativeOrAbsolute);
bi.EndInit();
// Set the image source.
simpleImage.Source = bi;
' Create the image element.
Dim simpleImage As New Image()
simpleImage.Width = 200
simpleImage.Margin = New Thickness(5)

' Create source.
Dim bi As New BitmapImage()
' BitmapImage.UriSource must be in a BeginInit/EndInit block.
bi.BeginInit()
bi.UriSource = New Uri("/sampleImages/cherries_larger.jpg", UriKind.RelativeOrAbsolute)
bi.EndInit()
' Set the image source.
simpleImage.Source = bi

Remarks

BitmapImage primarily exists to support Extensible Application Markup Language (XAML) syntax and introduces additional properties for bitmap loading that are not defined by BitmapSource.

BitmapImage implements the ISupportInitialize interface to optimize initialization on multiple properties. Property changes can only occur during object initialization. Call BeginInit to signal that initialization has begun and EndInit to signal that initialization has completed. After initialization, property changes are ignored.

BitmapImage objects created using the BitmapImage constructor are automatically initialized and property changes are ignored.

Constructors

BitmapImage()

Initializes a new instance of the BitmapImage class.

BitmapImage(Uri, RequestCachePolicy)

Initializes a new instance of the BitmapImage class with an image whose source is a Uri, and is cached according to the provided RequestCachePolicy.

BitmapImage(Uri)

Initializes a new instance of the BitmapImage class by using the supplied Uri.

Fields

CacheOptionProperty

Identifies the CacheOption dependency property.

CreateOptionsProperty

Identifies the CreateOptions dependency property.

DecodePixelHeightProperty

Identifies the DecodePixelHeight dependency property.

DecodePixelWidthProperty

Identifies the DecodePixelWidth dependency property.

RotationProperty

Identifies the Rotation dependency property.

SourceRectProperty

Identifies the SourceRect dependency property.

StreamSourceProperty

Identifies the StreamSource dependency property.

UriCachePolicyProperty

Identifies the UriCachePolicy dependency property.

UriSourceProperty

Identifies the UriSource dependency property.

Properties

BaseUri

Gets or sets a value that represents the base Uri of the current BitmapImage context.

CacheOption

Gets or sets the BitmapCacheOption to use for this instance of BitmapImage.

CanFreeze

Gets a value that indicates whether the object can be made unmodifiable.

(Inherited from Freezable)
CreateOptions

Gets or sets the BitmapCreateOptions for a BitmapImage.

DecodePixelHeight

Gets or sets the height, in pixels, that the image is decoded to.

DecodePixelWidth

Gets or sets the width, in pixels, that the image is decoded to.

DependencyObjectType

Gets the DependencyObjectType that wraps the CLR type of this instance.

(Inherited from DependencyObject)
Dispatcher

Gets the Dispatcher this DispatcherObject is associated with.

(Inherited from DispatcherObject)
DpiX

Gets the horizontal dots per inch (dpi) of the image.

(Inherited from BitmapSource)
DpiY

Gets the vertical dots per inch (dpi) of the image.

(Inherited from BitmapSource)
Format

Gets the native PixelFormat of the bitmap data.

(Inherited from BitmapSource)
HasAnimatedProperties

Gets a value that indicates whether one or more AnimationClock objects is associated with any of this object's dependency properties.

(Inherited from Animatable)
Height

Gets the height of the source bitmap in device-independent units (1/96th inch per unit).

(Inherited from BitmapSource)
IsDownloading

Gets a value that indicates whether the BitmapImage is currently downloading content.

IsFrozen

Gets a value that indicates whether the object is currently modifiable.

(Inherited from Freezable)
IsSealed

Gets a value that indicates whether this instance is currently sealed (read-only).

(Inherited from DependencyObject)
Metadata

Not supported. BitmapImage does not support the Metadata property and will throw a NotSupportedException.

Palette

Gets the color palette of the bitmap, if one is specified.

(Inherited from BitmapSource)
PixelHeight

Gets the height of the bitmap in pixels.

(Inherited from BitmapSource)
PixelWidth

Gets the width of the bitmap in pixels.

(Inherited from BitmapSource)
Rotation

Gets or sets the angle that this BitmapImage is rotated to.

SourceRect

Gets or sets the rectangle that is used as the source of the BitmapImage.

StreamSource

Gets or sets the stream source of the BitmapImage.

UriCachePolicy

Gets or sets a value that represents the caching policy for images that come from an HTTP source.

UriSource

Gets or sets the Uri source of the BitmapImage.

Width

Gets the width of the bitmap in device-independent units (1/96th inch per unit).

(Inherited from BitmapSource)

Methods

ApplyAnimationClock(DependencyProperty, AnimationClock, HandoffBehavior)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the specified HandoffBehavior is used.

(Inherited from Animatable)
ApplyAnimationClock(DependencyProperty, AnimationClock)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the SnapshotAndReplace handoff behavior is used.

(Inherited from Animatable)
BeginAnimation(DependencyProperty, AnimationTimeline, HandoffBehavior)

Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the specified HandoffBehavior is used.

(Inherited from Animatable)
BeginAnimation(DependencyProperty, AnimationTimeline)

Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the SnapshotAndReplace handoff behavior is used.

(Inherited from Animatable)
BeginInit()

Signals the start of the BitmapImage initialization.

CheckAccess()

Determines whether the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
CheckIfSiteOfOrigin()

Checks whether the bitmap source content is from a known site of origin. This method is used to make sure that pixel copying operations are safe.

(Inherited from BitmapSource)
ClearValue(DependencyProperty)

Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier.

(Inherited from DependencyObject)
ClearValue(DependencyPropertyKey)

Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey.

(Inherited from DependencyObject)
Clone()

Creates a modifiable clone of this BitmapImage, making deep copies of this object's values.

CloneCore(Freezable)

Makes this instance a deep copy of the specified BitmapSource. When copying dependency properties, this method copies resource references and data bindings (but they might no longer resolve) but not animations or their current values.

(Inherited from BitmapSource)
CloneCurrentValue()

Creates a modifiable clone of this BitmapImage object, making deep copies of this object's current values. Resource references, data bindings, and animations are not copied, but their current values are.

CloneCurrentValueCore(Freezable)

Makes this instance a modifiable deep copy of the specified BitmapSource using current property values. Resource references, data bindings, and animations are not copied, but their current values are.

(Inherited from BitmapSource)
CoerceValue(DependencyProperty)

Coerces the value of the specified dependency property. This is accomplished by invoking any CoerceValueCallback function specified in property metadata for the dependency property as it exists on the calling DependencyObject.

(Inherited from DependencyObject)
CopyPixels(Array, Int32, Int32)

Copies the bitmap pixel data into an array of pixels with the specified stride, starting at the specified offset.

(Inherited from BitmapSource)
CopyPixels(Int32Rect, Array, Int32, Int32)

Copies the bitmap pixel data within the specified rectangle into an array of pixels that has the specified stride starting at the specified offset.

(Inherited from BitmapSource)
CopyPixels(Int32Rect, IntPtr, Int32, Int32)

Copies the bitmap pixel data within the specified rectangle.

(Inherited from BitmapSource)
CreateInstance()

Initializes a new instance of the Freezable class.

(Inherited from Freezable)
CreateInstanceCore()

When implemented in a derived class, creates a new instance of the Freezable derived class.

(Inherited from Freezable)
EndInit()

Signals the end of the BitmapImage initialization.

Equals(Object)

Determines whether a provided DependencyObject is equivalent to the current DependencyObject.

(Inherited from DependencyObject)
Freeze()

Makes the current object unmodifiable and sets its IsFrozen property to true.

(Inherited from Freezable)
FreezeCore(Boolean)

Makes an instance of BitmapSource or a derived class immutable.

(Inherited from BitmapSource)
GetAnimationBaseValue(DependencyProperty)

Returns the non-animated value of the specified DependencyProperty.

(Inherited from Animatable)
GetAsFrozen()

Creates a frozen copy of the Freezable, using base (non-animated) property values. Because the copy is frozen, any frozen sub-objects are copied by reference.

(Inherited from Freezable)
GetAsFrozenCore(Freezable)

Makes this instance a clone of the specified BitmapSource object.

(Inherited from BitmapSource)
GetCurrentValueAsFrozen()

Creates a frozen copy of the Freezable using current property values. Because the copy is frozen, any frozen sub-objects are copied by reference.

(Inherited from Freezable)
GetCurrentValueAsFrozenCore(Freezable)

Makes this instance a frozen clone of the specified BitmapSource. Resource references, data bindings, and animations are not copied, but their current values are.

(Inherited from BitmapSource)
GetHashCode()

Gets a hash code for this DependencyObject.

(Inherited from DependencyObject)
GetLocalValueEnumerator()

Creates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject.

(Inherited from DependencyObject)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
GetValue(DependencyProperty)

Returns the current effective value of a dependency property on this instance of a DependencyObject.

(Inherited from DependencyObject)
InvalidateProperty(DependencyProperty)

Re-evaluates the effective value for the specified dependency property.

(Inherited from DependencyObject)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnChanged()

Called when the current Freezable object is modified.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject, DependencyProperty)

This member supports the Windows Presentation Foundation (WPF) infrastructure and is not intended to be used directly from your code.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject)

Ensures that appropriate context pointers are established for a DependencyObjectType data member that has just been set.

(Inherited from Freezable)
OnPropertyChanged(DependencyPropertyChangedEventArgs)

Overrides the DependencyObject implementation of OnPropertyChanged(DependencyPropertyChangedEventArgs) to also invoke any Changed handlers in response to a changing dependency property of type Freezable.

(Inherited from Freezable)
ReadLocalValue(DependencyProperty)

Returns the local value of a dependency property, if it exists.

(Inherited from DependencyObject)
ReadPreamble()

Ensures that the Freezable is being accessed from a valid thread. Inheritors of Freezable must call this method at the beginning of any API that reads data members that are not dependency properties.

(Inherited from Freezable)
SetCurrentValue(DependencyProperty, Object)

Sets the value of a dependency property without changing its value source.

(Inherited from DependencyObject)
SetValue(DependencyProperty, Object)

Sets the local value of a dependency property, specified by its dependency property identifier.

(Inherited from DependencyObject)
SetValue(DependencyPropertyKey, Object)

Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property.

(Inherited from DependencyObject)
ShouldSerializeProperty(DependencyProperty)

Returns a value that indicates whether serialization processes should serialize the value for the provided dependency property.

(Inherited from DependencyObject)
ToString()

Creates a string representation of this object based on the current culture.

(Inherited from ImageSource)
ToString(IFormatProvider)

Creates a string representation of this object based on the IFormatProvider passed in. If the provider is null, the CurrentCulture is used.

(Inherited from ImageSource)
VerifyAccess()

Enforces that the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
WritePostscript()

Raises the Changed event for the Freezable and invokes its OnChanged() method. Classes that derive from Freezable should call this method at the end of any API that modifies class members that are not stored as dependency properties.

(Inherited from Freezable)
WritePreamble()

Verifies that the Freezable is not frozen and that it is being accessed from a valid threading context. Freezable inheritors should call this method at the beginning of any API that writes to data members that are not dependency properties.

(Inherited from Freezable)

Events

Changed

Occurs when the Freezable or an object it contains is modified.

(Inherited from Freezable)
DecodeFailed

Occurs when the image fails to load, due to a corrupt image header.

(Inherited from BitmapSource)
DownloadCompleted

Occurs when the bitmap content has been completely downloaded.

(Inherited from BitmapSource)
DownloadFailed

Occurs when the bitmap content failed to download.

(Inherited from BitmapSource)
DownloadProgress

Occurs when the download progress of the bitmap content has changed.

(Inherited from BitmapSource)

Explicit Interface Implementations

IFormattable.ToString(String, IFormatProvider)

Formats the value of the current instance using the specified format.

(Inherited from ImageSource)

Applies to

See also