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BitmapCreateOptions Enum

Definition

Specifies initialization options for bitmap images.

This enumeration supports a bitwise combination of its member values.

public enum class BitmapCreateOptions
[System.Flags]
public enum BitmapCreateOptions
[<System.Flags>]
type BitmapCreateOptions = 
Public Enum BitmapCreateOptions
Inheritance
BitmapCreateOptions
Attributes

Fields

Name Value Description
None 0

No BitmapCreateOptions are specified. This is the default value.

PreservePixelFormat 1

Ensures that the PixelFormat a file is stored in is the same as it is loaded to.

DelayCreation 2

Causes a BitmapSource object to delay initialization until it is necessary. This is useful when dealing with collections of images.

IgnoreColorProfile 4

Causes a BitmapSource to ignore an embedded color profile.

IgnoreImageCache 8

Loads images without using an existing image cache. This option should only be selected when images in a cache need to be refreshed.

Examples

The following example demonstrates how to instantiate a BitmapImage and specify a BitmapCreateOptions enumeration value.

// Define a BitmapImage.
Image myImage = new Image();
BitmapImage bi = new BitmapImage();

// Begin initialization.
bi.BeginInit();

// Set properties.
bi.CacheOption = BitmapCacheOption.OnDemand;
bi.CreateOptions = BitmapCreateOptions.DelayCreation;
bi.DecodePixelHeight = 125;
bi.DecodePixelWidth = 125;
bi.Rotation = Rotation.Rotate90;
MessageBox.Show(bi.IsDownloading.ToString());
bi.UriSource = new Uri("smiley.png", UriKind.Relative);

// End initialization.
bi.EndInit();
myImage.Source = bi;
myImage.Stretch = Stretch.None;
myImage.Margin = new Thickness(5);
' Define a BitmapImage.
Dim myImage As New Image()
Dim bi As New BitmapImage()

' Begin initialization.
bi.BeginInit()

' Set properties.
bi.CacheOption = BitmapCacheOption.OnDemand
bi.CreateOptions = BitmapCreateOptions.DelayCreation
bi.DecodePixelHeight = 125
bi.DecodePixelWidth = 125
bi.Rotation = Rotation.Rotate90
MessageBox.Show(bi.IsDownloading.ToString())
bi.UriSource = New Uri("smiley.png", UriKind.Relative)

' End initialization.
bi.EndInit()
myImage.Source = bi
myImage.Stretch = Stretch.None
myImage.Margin = New Thickness(5)

Remarks

If PreservePixelFormat is not set, the PixelFormat of the image is chosen by the system depending on what the system determines will yield the best performance. Enabling this option preserves the file format but may result in lesser performance.

If IgnoreColorProfile is set, calls to methods such as CopyPixels(Array, Int32, Int32) will not return color-corrected bits.

If IgnoreImageCache is set, any existing entries in the image cache are replaced even if they share the same Uri.

Applies to

See also