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RenderTargetBitmap Class

Definition

Converts a Visual object into a bitmap.

public ref class RenderTargetBitmap sealed : System::Windows::Media::Imaging::BitmapSource
public sealed class RenderTargetBitmap : System.Windows.Media.Imaging.BitmapSource
type RenderTargetBitmap = class
    inherit BitmapSource
Public NotInheritable Class RenderTargetBitmap
Inherits BitmapSource
Inheritance

Examples

The following example shows how to use RenderTargetBitmap to render text as an image.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Globalization;

namespace SDKSample
{
    public partial class RenderTargetBitmapExample : Page
    {
        public RenderTargetBitmapExample()
        {

            Image myImage = new Image();
            FormattedText text = new FormattedText("ABC",
                    new CultureInfo("en-us"),
                    FlowDirection.LeftToRight,
                    new Typeface(this.FontFamily, FontStyles.Normal, FontWeights.Normal, new FontStretch()),
                    this.FontSize,
                    this.Foreground);

            DrawingVisual drawingVisual = new DrawingVisual();
            DrawingContext drawingContext = drawingVisual.RenderOpen();
            drawingContext.DrawText(text, new Point(2, 2));
            drawingContext.Close();

            RenderTargetBitmap bmp = new RenderTargetBitmap(180, 180, 120, 96, PixelFormats.Pbgra32);
            bmp.Render(drawingVisual);
            myImage.Source = bmp;

            // Add Image to the UI
            StackPanel myStackPanel = new StackPanel();
            myStackPanel.Children.Add(myImage);
            this.Content = myStackPanel;
        }
    }
}
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Globalization

Namespace SDKSample

    Class RenderTargetBitmapExample
        Inherits Page

        Public Sub New()

            Dim myImage As New Image()
            Dim [text] As New FormattedText("ABC", New CultureInfo("en-us"), System.Windows.FlowDirection.LeftToRight, New Typeface(Me.FontFamily, FontStyles.Normal, FontWeights.Normal, New FontStretch()), Me.FontSize, Me.Foreground)

            Dim drawingVisual As New DrawingVisual()
            Dim drawingContext As DrawingContext = drawingVisual.RenderOpen()
            drawingContext.DrawText([text], New System.Windows.Point(2, 2))
            drawingContext.Close()

            Dim bmp As New RenderTargetBitmap(180, 180, 120, 96, PixelFormats.Pbgra32)
            bmp.Render(drawingVisual)
            myImage.Source = bmp
            ' Add Image to the UI
            Dim myStackPanel As New StackPanel()
            myStackPanel.Children.Add(myImage)
            Me.Content = myStackPanel

        End Sub
    End Class
End Namespace 'ImagingSnippetGallery

Constructors

RenderTargetBitmap(Int32, Int32, Double, Double, PixelFormat)

Initializes a new instance of the RenderTargetBitmap class that has the specified parameters.

Properties

CanFreeze

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

(Inherited from Freezable)
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 BitmapSource content is currently downloading.

(Inherited from BitmapSource)
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

Gets the metadata that is associated with this bitmap image.

(Inherited from BitmapSource)
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)
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)
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)
Clear()

Clears the render target and sets all pixels to transparent black.

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 BitmapSource, making deep copies of this object's values. 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)
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 BitmapSource object, making deep copies of this object's current values. Resource references, data bindings, and animations are not copied, but their current values are.

(Inherited from BitmapSource)
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)
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)
Render(Visual)

Renders the Visual object.

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