Image Image Image Class

Represents a control that displays an image. The image source is specified by referring to an image file, using several supported formats. The image source can also be set with a stream. See Remarks for the list of supported image source formats.

Syntax

Declaration

public sealed class Imagepublic sealed class ImagePublic NotInheritable Class Image
<Image .../>

Inheritance Hierarchy

Inherited Members

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Remarks

Image file formats

An Image can display these image file formats:+ Joint Photographic Experts Group (JPEG)

  • Portable Network Graphics (PNG)
  • bitmap (BMP)
  • Graphics Interchange Format (GIF)
  • Tagged Image File Format (TIFF)
  • JPEG XR
  • icons (ICO)
Note

Icon files supported on Windows only. Not supported on Windows Phone 8.1

Starting in Windows 10, version 1607, the Image element supports animated Graphics Interchange Format (GIF) images. When you use a BitmapImage as the image Source, you can access BitmapImage API to control playback of the animated Graphics Interchange Format (GIF) image. For more info, see the Remarks on the BitmapImage class page.

Note

Animated Graphics Interchange Format (GIF) support is available when your app is compiled for Windows 10, version 1607 and running on version 1607 (or later). When your app is compiled for or runs on previous versions, the first frame of the Graphics Interchange Format (GIF) is shown, but it is not animated.

Setting Image.Source

To set the image source file that an Image displays, you set its Source property, either in XAML or in code. Here's a simple example of setting Source in XAML:

<Image Width="200" Source="Images/myimage.png"/>

This usage is setting Source by Uniform Resource Identifier (URI), which is a shortcut that's enabled by XAML. Note that the Uniform Resource Identifier (URI) here appears to be a relative Uniform Resource Identifier (URI); supporting partial Uniform Resource Identifier (URI) is another XAML shortcut. The root of this Uniform Resource Identifier (URI) is the base folder for an app project. This is usually the same location that the XAML file containing the Image tag is loaded from. In this example, the image source file is in an Images subfolder within the app's file structure.

Setting the Source property is inherently an asynchronous action. Because it's a property, there isn't an awaitable syntax, but for most scenarios you don't need to interact with the asynchronous aspects of image loading. The framework will wait for the image source to be returned, and will start a layout cycle when the image source file is available and decoded.

Setting the source to a Uniform Resource Identifier (URI) value that can't be resolved to a valid image source file doesn't throw an exception. Instead, it fires an ImageFailed event. You can write an ImageFailed handler and attach it to the Image object, and possibly use the ErrorMessage in event data to determine the nature of the failure. An error in decoding can also fire ImageFailed. If you want to verify that an image source file was loaded correctly, you can handle the ImageOpened event on the Image element.

You typically use image source files that you have included as part of your app download package. For large files, there might be a very small delay while the image source file is decoded, if this is the first time the source is used. For more info on app resources and how to package image source files in an app package, see Defining app resources.

You can also use image source files that aren't part of the app, for example images from external servers. These images are downloaded by an internal HTTP request, and then decoded. If the image source file is a large file, or if there are connection issues, there might be a delay before an external image can be displayed in an Image element.

Setting Image.Source using code

If you create an Image object using code, call the default constructor, then set the Source property. Setting the Source property requires an instance of the BitmapImage class, which you also must construct. If your image source is a file referenced by Uniform Resource Identifier (URI), use the @Windows.UI.Xaml.Media.Imaging.BitmapImage.#ctor(Windows.Foundation.Uri) constructor that takes a Uniform Resource Identifier (URI) parameter. When you reference local content, you must include the ms-appx: scheme in the absolute Uniform Resource Identifier (URI) that you use as the @Windows.UI.Xaml.Media.Imaging.BitmapImage.#ctor(Windows.Foundation.Uri) constructor parameter. In code, you don't get the processing shortcuts for combining relative Uniform Resource Identifier (URI) parts and the ms-appx: scheme that happens automatically if you specify Source as a XAML attribute. Instead you must explicitly construct an absolute Uniform Resource Identifier (URI) with the appropriate scheme. You typically use the ms-appx: scheme for an image file that's packaged as part of your app.

Tip

If you're using C# or Microsoft Visual Basic, you can get the BaseUri property of the Image, and pass that as the baseUri parameter for System.Uri constructors that combine a Uniform Resource Identifier (URI) base location and a relative path within that location.

Here's an example of setting Source in C#. In this example, the Image object was created in XAML but doesn't have a source or any other property values; instead these values are provided at run-time when the Image is loaded from XAML.

void Image_Loaded(object sender, RoutedEventArgs e)
{
    Image img = sender as Image; 
    BitmapImage bitmapImage = new BitmapImage();
    img.Width = bitmapImage.DecodePixelWidth = 80; //natural px width of image source
    // don't need to set Height, system maintains aspect ratio, and calculates the other
    // dimension, so long as one dimension measurement is provided
    bitmapImage.UriSource = new Uri(img.BaseUri,"Images/myimage.png");
}

Using a stream source for an Image source

If your image source is a stream, you must write code that sets your Image instance to use the stream. This can't be done in XAML alone. Construct the Image to use, or reference an existing Image instance (which might have been defined in XAML markup, but without a source). Then use the async SetSourceAsync(Windows.Storage.Streams.IRandomAccessStream) method of BitmapImage to define the image information from a stream, passing the stream to use as the streamSource parameter. Using a stream for an image source is fairly common. For example, if your app enables a user to choose an image file using a FileOpenPicker control, the object you get that represents the file the user chose can be opened as a stream, but doesn't provide a Uniform Resource Identifier (URI) reference to the file.

In this example, the code is already awaitable because it's waiting for the user to choose a file and it only runs after that happens. The stream to use comes from OpenAsync(Windows.Storage.FileAccessMode,Windows.Storage.StorageOpenOptions) after a StorageFile instance is returned from the async picker actions.

FileOpenPicker open = new FileOpenPicker(); 
// Open a stream for the selected file 
StorageFile file = await open.PickSingleFileAsync(); 
// Ensure a file was selected 
if (file != null) 
{ 
    using (IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read)) 
    { 
        // Set the image source to the selected bitmap 
         BitmapImage bitmapImage = new BitmapImage(); 
         bitmapImage.DecodePixelWidth = 600; //match the target Image.Width, not shown
         await bitmapImage.SetSourceAsync(fileStream); 
         Scenario2Image.Source = bitmapImage; 
    } 
}
Tip

If you're using C# or Microsoft Visual Basic, streams can use the System.IO.Stream type that you may be familiar with from previous Microsoft .NET programming experience. You can call the AsStream extension method as an instance method on any object of type IRandomAccessStream that you've obtained from a Windows Runtime API. The previous example used IRandomAccessStream for parameter passing and didn't need to use AsStream. But if you ever need to manipulate the stream, AsStream is there as a utility to convert to a System.IO.Stream if you need it.

See XAML images sample for more example code.

Image files and performance

Large image files can impact performance because they load into memory. If you are referencing an image file where you know that the source file is a large, high resolution image, but your app is displaying it in a UI region that's smaller than the image's natural size, you should set the DecodePixelWidth property, or DecodePixelHeight. The DecodePixel* properties enable you to pass information directly to the format-specific codec, and the codec can use this information to decode more efficiently and to a smaller memory footprint. Set DecodePixelWidth to the same pixel width of the area that you want your app to actually display. In other words, DecodePixelWidth for the BitmapImage source should be the same value as the Width or ActualWidth of the Image control that displays that source.

You can either set DecodePixelWidth, or set DecodePixelHeight. If you set one of these two properties, the system calculates the matching property to maintain the correct aspect ratio. You can also set both properties, but you typically should use values that maintain that aspect ratio. If you want to change aspect ratios there are better ways to do so, for example using a TranslateTransform as a RenderTransform.

To set DecodePixelWidth (or DecodePixelHeight ) in XAML, you must use a slightly more verbose XAML syntax that includes an explicit BitmapImage element as a property element value, like this:

<Image>
  <Image.Source>
    <BitmapImage DecodePixelWidth="200" UriSource="images/myimage.png"/>
  </Image.Source>
</Image>

DecodePixelWidth (or DecodePixelHeight ) are properties of BitmapImage, so you need an explicit BitmapImage XAML object element in order to set the DecodePixel* properties as attributes in XAML.

If you are creating an Image instance in code, you are probably already creating a BitmapImage instance as a value to provide for the Source property, so just set DecodePixelWidth (or DecodePixelHeight ) on the BitmapImage instance before you set the UriSource property. The DecodePixelType property also affects how pixel values are interpreted by the decode operations.

To prevent images from being decoded more than once, assign image source property from Uniform Resource Identifier (URI) rather than using memory streams whenever you can. The XAML framework can associate the same Uniform Resource Identifier (URI) in multiple places with one decoded image, but it cannot do the same for multiple memory streams even if they contain the same data.

You can remove image files from the image cache by setting all associated Source values to null.

For more info on the Image class and performance, see Optimize animations and media.

Image file encoding and decoding

The underlying codec support for image files is supplied by Windows Imaging Component (WIC) API. For more info on specific image formats as documented for the codecs, see Native WIC Codecs.

The API for Image, BitmapImage and BitmapSource doesn't include any dedicated methods for encoding and decoding of media formats. All of the decoding operations are built-in as actions that happen when the source is set or reset. This makes the classes easier to use for constructing UI, because they have a default set of supported source file formats and decoding behavior. Classes such as BitmapImage expose some of the decoding options and logic as part of event data for ImageOpened or ImageFailed events. If you need advanced image file decoding, or image encoding, you should use the API from the Windows.Graphics.Imaging namespace. You might need these API if your app scenario involves image file format conversions, or manipulation of an image where the user can save the result as a file. The encoding API are also supported by the Windows Imaging Component (WIC) component of Windows.

Image width and height

The Image class inherits the Width and Height properties from FrameworkElement, and these properties potentially control the size that your Image control will render when it displays in UI. If you don't set a Width or a Height, then the width and height is determined by the natural size of the image source. For example, if you load a bitmap image that is 300 pixels high and 400 pixels wide, as recorded in its source file format, these measurements are used for the width and height when the Image control calculates its natural size. You can check ActualHeight and ActualWidth at run time after the image renders to get the measurement information. Or, you can handle ImageOpened and check image file properties such as PixelHeight and PixelWidth immediately before the image renders.

If you set just one of the Width or Height properties but not both, then the system can use that dimension as guidance and calculate the other one, preserving the aspect ratio. If you're not sure of the source file dimensions, pick the dimension that's the most important to control in your layout scenario and let the system calculate the other dimension, and then the layout behavior of the container will typically adapt the layout to fit.

If you don't set Width and/or Height, and leave the image as its natural size, the Stretch property for the image can control how the image source file will fill the space you specify as Width and Height. The default Stretch value is Uniform, which preserves aspect ratio when it fits the image into a layout container. If the container's dimensions don't have the same aspect ratio, then there will be empty space that's still part of Image but isn't showing any image pixels, at least while using the Uniform value for Stretch. UniformToFill for Stretch won't leave empty space but might clip the image if dimensions are different. Fill for Stretch won't leave empty space, but might change the aspect ratio. You can experiment with these values to see what's best for image display in your layout scenario. Also, be aware that certain layout containers might size an image that has no specific Width and Height to fill the entire layout space, in which case you can choose to set specific sizes on either the image or the container for it.

NineGrid

Using the NineGrid technique is another option for sizing images that have a different natural size than your display area, if the image has regions that should not be scaled uniformly. For example you can use a background image that has an inherent border that should only stretch in one dimension, and corners that shouldn't stretch at all, but the image center can stretch to fit the layout requirements in both dimensions. For more info, see NineGrid.

Resource qualification and localization for Image

Image source files and scaling

You should create your image sources at several recommended sizes, to ensure that your app looks great when Windows 8 scales it. When specifying a Source for an Image, you can use a naming convention for resources that will use the correct resource for device-specific scaling factors. This is determined by the app automatically at run-time. For specifics of the naming conventions to use and more info, see Quickstart: Using file or image resources.

For more info on how to design images properly for scaling, see UX guidelines for layout and scaling.

Using unqualified resources

Unqualified resources is a technique you can use where the basic resource reference refers to a default resource, and the resource management process can find the equivalent localized resource automatically. You can use automatic handling for accessing unqualified resources with current scale and culture qualifiers, or you can use ResourceManager and ResourceMap with qualifiers for culture and scale to obtain the resources directly. For more info see Resource management system.

FlowDirection for Image

If you set FlowDirection as RightToLeft for an Image, the visual content of an Image is flipped horizontally. However, an Image element does not inherit the FlowDirection value from any parent element. Typically you only want image-flipping behavior in images that are relevant to layout, but not necessarily to elements that have embedded text or other components that wouldn't make sense flipped for a right-to-left audience. To get image-flip behavior, you must set the FlowDirection element on the Image element specifically to RightToLeft, or set the FlowDirection property in code-behind. Consider identifying the Image element by x:Uid directive, and specifying FlowDirection values as a Windows Runtime resource, so that your localization experts can change this value later without changing the XAML or code.

The Image class and accessibility

The Image class is not a true control class in that it is not a descendant class of Control. You can't call focus to an Image element, or place an Image element in a tab sequence. For more info on the accessibility aspects of using images and the Image element in your UI, see Basic accessibility information.

Windows 8 behavior

For Windows 8, resources can use a resource qualifier pattern to load different resources depending on device-specific scaling. However, resources aren't automatically reloaded if the scaling factor changes while the app is running. In this case apps would have to take care of reloading resources, by handling the DpiChanged event (or the deprecated LogicalDpiChanged event) and using ResourceManager API to manually reload the resource that's appropriate for the new scaling factor. Starting with Windows 8.1, any resource that was originally retrieved for your app is automatically re-evaluated if the scaling factor changes while the app is running. In addition, when that resource is the image source for an Image object, then one of the source-load events (ImageOpened or ImageFailed ) is fired as a result of the system's action of requesting the new resource and then applying it to the Image. The scenario where a run-time scale change might happen is if the user moves your app to a different monitor when more than one is available.

If you migrate your app code from Windows 8 to Windows 8.1 you may want to account for this behavior change, because it results in ImageOpened or ImageFailed events that happen at run-time when the scale change is handled, even in cases where the Source is set in XAML. Also, if you did have code that handled DpiChanged /LogicalDpiChanged and reset the resources, you should examine whether that code is still needed given the new Windows 8.1 automatic reload behavior.

Apps that were compiled for Windows 8 but running on Windows 8.1 continue to use the Windows 8 behavior.

Constructors summary

Initializes a new instance of the Image class.

Properties summary

Gets or sets a value for a nine-grid metaphor that controls how the image can be resized. The nine-grid metaphor enables you to stretch edges and corners of an image differently than its center. See Remarks for more info and an illustration.

Identifies the NineGrid dependency property.

Gets the information that is transmitted if the Image is used for a Play To scenario.

Identifies the PlayToSource dependency property.

Gets or sets the source for the image.

Identifies the Source dependency property.

Gets or sets a value that describes how an Image should be stretched to fill the destination rectangle.

Identifies the Stretch dependency property.

Methods summary

Returns a mask that represents the alpha channel of an image as a CompositionBrush.

Returns the image as a CastingSource.

Events summary

Occurs when there is an error associated with image retrieval or format.

Occurs when the image source is downloaded and decoded with no failure. You can use this event to determine the natural size of the image source.

Constructors

  • Image()
    Image()
    Image()
    Image()

    Initializes a new instance of the Image class.

    public Image()public Image()Public Function Image() As

Properties

  • NineGrid
    NineGrid
    NineGrid
    NineGrid

    Gets or sets a value for a nine-grid metaphor that controls how the image can be resized. The nine-grid metaphor enables you to stretch edges and corners of an image differently than its center. See Remarks for more info and an illustration.

    public Thickness NineGrid { get; set; }public Thickness NineGrid { get; set; }Public ReadWrite Property NineGrid As Thickness
    <Image NineGrid="left,top,right,bottom" />
    

    Property Value

    Remarks

    When you use nine-grid rendering, you can specify how different areas of the image are stretched. This feature is useful for preserving the detail on image corners when an image scales or stretches.

    Nine-grid rendering divides an image into a grid of nine sections:

    A grid of nine sections. Nine-grid rendering enables you to preserve the original dimensions of the corners (boxes 1, 3, 7, and 9). The top and bottom (boxes 2 and 8) are stretched horizontally only, and the sides (boxes 4 and 6) are stretched vertically only. The center (box 5) is stretched in both dimensions. To use nine-grid rendering, you create an Image element and specify a value for the NineGrid property—pixel values for the lengths of the left, top, right, and bottom sides of the grid. In XAML, you specify the NineGrid attribute value as a string that specifies pixel values for the sides in left, top, right, bottom order. Internally, this syntax creates a Thickness object that represents this type of measurement. If you want a uniform value, you can specify just one value that's applied to all four edges.

    Applying nine-grid rendering is very useful when the image itself includes some type of border or edge decoration embedded within the image source. For example, imagine you're using an image source for a Button that has the outline as part of an image with transparency. You might want the center area that contains an icon to stretch. But if you stretch the corners you might get aliasing artifacts from rounded corners. Or the border sides might get too thick and wouldn't look as good when scaled. To prevent that, you could use a NineGrid with uniform values that always keep the pixel size of the border the same size as in the image source.

    Either in code or in XAML, the values for the Thickness that you use to set the NineGrid property are device-independent pixel values.

    Here's example XAML for an Image element using a NineGrid value:

    <Image Source="Images/9grid.bmp" NineGrid="30,20,30,20" />
    

    A NineGrid value is only relevant for image rendering if the image does not have specific values set for Width and/or Height, and where the image is being stretched (image is rendered into a larger container space and the value for Stretch is not** None**).

  • NineGridProperty
    NineGridProperty
    NineGridProperty
    NineGridProperty

    Identifies the NineGrid dependency property.

    public static DependencyProperty NineGridProperty { get; }public static DependencyProperty NineGridProperty { get; }Public Static ReadOnly Property NineGridProperty As DependencyProperty

    Property Value

  • PlayToSource
    PlayToSource
    PlayToSource
    PlayToSource

    Gets the information that is transmitted if the Image is used for a Play To scenario.

    public PlayToSource PlayToSource { get; }public PlayToSource PlayToSource { get; }Public ReadOnly Property PlayToSource As PlayToSource

    Property Value

    Remarks

    You can use Play To to enable users to easily stream audio, video, or images from their computer to devices in their home network. PlayToSource is specifically for the XAML images version of this scenario.

    Play To is part of the Devices charm. Users open the Devices charm to select devices from their home network that they can stream the media content to. When a user selects a Play To target from the Devices charm, Play To fires the SourceRequested event. Play To then streams the media element that was passed to the SetSource(Windows.Media.PlayTo.PlayToSource) method to the target device that the user has selected. PlayToSource provides the PlayToSource controller object that the PlayToManager can use in this scenario. For an example of how to use Play To in an application, see PlayReady DRM.

  • PlayToSourceProperty
    PlayToSourceProperty
    PlayToSourceProperty
    PlayToSourceProperty

    Identifies the PlayToSource dependency property.

    public static DependencyProperty PlayToSourceProperty { get; }public static DependencyProperty PlayToSourceProperty { get; }Public Static ReadOnly Property PlayToSourceProperty As DependencyProperty

    Property Value

  • Source
    Source
    Source
    Source

    Gets or sets the source for the image.

    public ImageSource Source { get; set; }public ImageSource Source { get; set; }Public ReadWrite Property Source As ImageSource
    <Image Source="uri"/>
    

    Property Value

    • An object that represents the image source file for the drawn image. Typically you set this with a BitmapImage object, constructed with the Uniform Resource Identifier (URI) that describes the path to a valid image source file. Or, you can initialize a BitmapSource with a stream, perhaps a stream from a storage file.

    Remarks

    Setting the Source property is inherently an asynchronous action. Because it's a property, there isn't an awaitable syntax, but for most scenarios you don't need to interact with the asynchronous aspects of image source file loading. The framework will wait for the image source to be returned, and will rerun layout when the image source file becomes available.

    Setting the source to a Uniform Resource Identifier (URI) value that can't be resolved to a valid image source file does not throw an exception. Instead, it fires an ImageFailed event. Decoding failures also fire ImageFailed. You can write an ImageFailed handler and attach it to the Image object to detect this, and possibly use the ErrorMessage in event data to determine the nature of the failure. Also, if you want to verify that an image source file was loaded correctly, you can handle the ImageOpened event on the Image element.

    Setting Source in XAML

    You can set the Source property as an attribute in XAML. In this case, you're setting the Source attribute value as a Uniform Resource Identifier (URI) string that describes the location of the source image file. This behavior relies on underlying type conversion that processes the string as a Uniform Resource Identifier (URI), and calls the equivalent of the @Windows.UI.Xaml.Media.Imaging.BitmapImage.#ctor(Windows.Foundation.Uri) constructor. Setting the Source property using a Uniform Resource Identifier (URI) string is a shortcut enabled by XAML. Note that the Uniform Resource Identifier (URI) here appears to be a relative Uniform Resource Identifier (URI); supporting partial Uniform Resource Identifier (URI) is another XAML shortcut.

    <Image Width="200" Source="Images/myImage.png"/>
    

    The XAML parser interprets any strings that represent a relative Uniform Resource Identifier (URI) using the base Uniform Resource Identifier (URI) of the XAML page that is being parsed. For example, if you specify a value "Images/myImage.png" in XAML, that string is interpreted as a relative path suffix that is appended to the base Uniform Resource Identifier (URI) location within the app package where the XAML page itself exists. If the previous Image element is added to a page that’s in the root of the app package, the Uniform Resource Identifier (URI) is interpreted as ms-appx:///Images/myImage.png. If the Image is added to a page that’s in a Pages folder in the app, the Uniform Resource Identifier (URI) is interpreted as ms-appx:///Pages/Images/myImage.png.

    If the source image is not part of the app package, you must use an absolute Uniform Resource Identifier (URI) to set the Source property in XAML. For more info, see How to load file resources, and examples later in this document.

    A property element syntax in XAML is also possible, specifying a BitmapImage object element with valid source as the property value.

    Setting Source in code

    To set the Source property in code requires an instance of BitmapImage (or BitmapSource ), which you also must construct. If your image source is a stream, use the async SetSourceAsync(Windows.Storage.Streams.IRandomAccessStream) method of BitmapImage to define the image information from the stream. For more info, see the section.

    If your image source is a file referenced by Uniform Resource Identifier (URI), set the UriSource property, or use the @Windows.UI.Xaml.Media.Imaging.BitmapImage.#ctor(Windows.Foundation.Uri) constructor that takes a Uniform Resource Identifier (URI) parameter. The Windows Runtime enforces that a Uniform Resource Identifier (URI) must be absolute; you can't use relative Uniform Resource Identifier (URI) in Windows Runtime code. If you are using a .NET Framework System.Uri value, and you use a signature that requires a UriKind value, make sure to specify Absolute.

    When you reference local content, you must include the ms-appx: scheme in the absolute Uniform Resource Identifier (URI) that you use as the UriSource. In code, you don't get the processing shortcuts for combining relative Uniform Resource Identifier (URI) parts and the ms-appx: scheme that happens automatically if you specify Source as a XAML attribute. Instead you must explicitly construct an absolute Uniform Resource Identifier (URI) with the appropriate scheme.

    Here's how to set the source to an image from the app package.

    
    Image img = new Image();
    BitmapImage bitmapImage = new BitmapImage();
    Uri uri = new Uri("ms-appx:///Assets/Logo.png");
    bitmapImage.UriSource = uri;
    img.Source = bitmapImage;
    
    // OR
    
    Image img = new Image();
    img.Source = new BitmapImage(new Uri("ms-appx:///Assets/Logo.png"));
    
    auto img = ref new Image();
    auto bitmapImage = ref new Windows::UI::Xaml::Media::Imaging::BitmapImage();
    auto uri = ref new Windows::Foundation::Uri("ms-appx:///Assets/Logo.png");
    bitmapImage->UriSource = uri;
    img->Source = bitmapImage;
    
    // OR
    
    auto img = ref new Image();
    img->Source = ref new BitmapImage(ref new Windows::Foundation::Uri("ms-appx:///Assets/Logo.png"));
    

    If you need to ensure that the Image control is ready before trying to use it in code, handle the Loaded event, and set the Source property in the event handler.

    Note

    The Loaded event occurs when the Image control is loaded into the XAML page. The ImageOpened event occurs when the image file is opened in the Image control.

    Here's an example of setting Source in the handler for the Loaded event. In this example, the Image object was created in XAML but doesn't have a source or any other property values; instead these values are provided at run-time when the Image is loaded from XAML.

    <Image Loaded="Image_Loaded"/>
    
    void Image_Loaded(object sender, RoutedEventArgs e)
    {
        Image img = sender as Image;
        if (img != null)
        {
            BitmapImage bitmapImage = new BitmapImage();
            img.Width = bitmapImage.DecodePixelWidth = 280;
            bitmapImage.UriSource = new Uri("ms-appx:///Assets/Logo.png");
            img.Source = bitmapImage;
        }
    }
    
    void App1::MainPage::Image_Loaded(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
    {
     auto img = dynamic_cast<Image^>(sender);
     if (img != nullptr)
     {
      auto bitmapImage = ref new BitmapImage();
      img->Width = 280; bitmapImage->DecodePixelWidth = 280;
      bitmapImage->UriSource = ref new Uri("ms-appx:///Assets/Logo.png");
      img->Source = bitmapImage;
     }
    }
    

    You can handle the ImageOpened event if there are any timing issues with retrieving or decoding the image source, where you might need alternate content to display until the image source is available. See XAML images sample for example code.

    Using a relative URI in code

    We saw previously that the XAML parser interprets a relative Uniform Resource Identifier (URI) using the base Uniform Resource Identifier (URI) of the XAML page that is being parsed. To achieve the same result in code, you can construct a Uri using one of the constructors that creates a Uniform Resource Identifier (URI) by combining an absolute base and then a relative path within that location. For the first parameter, call BaseUri on Page where the Image is loaded. (You can also call BaseUri on the Image instance where you are setting the source, or another element on the page. See the Caution below.) This creates a Uniform Resource Identifier (URI) with the ms-appx: scheme and adds the path that is part of the XAML page's location. For the second parameter, pass the relative Uniform Resource Identifier (URI) string that describes the source image location.

    In C# or Microsoft Visual Basic, the Uri type is projected as System.Uri, so use the System.Uri(Uri, String) constructor that takes a string as the second parameter. In Visual C++ component extensions (C++/CX) use @Windows.Foundation.Uri.#ctor(System.String).

    <Image x:Name="capturedPhoto"/>
    
    
    BitmapImage bitmapImage = new BitmapImage();
    // Call BaseUri on the root Page element and combine it with a relative path
    // to consruct an absolute URI.
    bitmapImage.UriSource = new Uri(this.BaseUri, "Assets/placeholder.png");
    capturedPhoto.Source = bitmapImage;
    
    
    auto bitmapImage = ref new Windows::UI::Xaml::Media::Imaging::BitmapImage();
    // Call BaseUri on the root Page element and combine it with a relative path
    // to consruct an absolute URI.
    bitmapImage->UriSource = ref new Windows::Foundation::Uri(BaseUri->AbsoluteUri, "Assets/placeholder.png");
    capturedPhoto->Source = bitmapImage;
    
    Note

    If you instantiate a new Image in code, the BaseUri property is null until the Image is added to the visual tree of the a page. For example, the following code throws an ArgumentNull exception. To avoid the exception, add the Image to the visual tree before setting the Source property.

    This example throws an exception because it calls BaseUri on the Image before the Image is added to the page. It's assumed that 'stackPanel1' is a StackPanel element declared in XAML.

    
    Image img = new Image();
    BitmapImage bitmapImage = new BitmapImage();
    
    // AN EXCEPTION IS THROWN BECAUSE img.BaseUri IS NULL AT THIS POINT.
    Uri uri = new Uri(img.BaseUri, "Assets/Logo.png");
    
    bitmapImage.UriSource = uri;
    img.Source = bitmapImage;
    stackPanel1.Children.Add(img);
    
    auto img = ref new Image();
    auto bitmapImage = ref new Windows::UI::Xaml::Media::Imaging::BitmapImage();
    
    // AN EXCEPTION IS THROWN BECAUSE img->BaseUri IS NULL AT THIS POINT.
    auto uri = ref new Windows::Foundation::Uri(img->BaseUri->AbsoluteUri, "Assets/Logo.png");
    
    bitmapImage->UriSource = uri;
    img->Source = bitmapImage;
    stackPanel1->Children->Append(img);
    

    To avoid this error, you can call BaseUri on the Page itself, as shown previously, or add the Image to the page before calling BaseUri, as shown here.

    In this example, the Image is added to the page before the call to BaseUri, so BaseUri is not null. It's assumed that 'stackPanel1' is a StackPanel element declared in XAML.

    
    Image img = new Image();
    // Add the image to the page.
    stackPanel1.Children.Add(img);
    
    BitmapImage bitmapImage = new BitmapImage();
    // img.BaseUri in not null because img has been added to the page.
    Uri uri = new Uri(img.BaseUri, "Assets/Logo.png");
    bitmapImage.UriSource = uri;
    img.Source = bitmapImage;
    
    auto img = ref new Image();
    // Add the image to the page.
    stackPanel1->Children->Append(img);
    
    auto bitmapImage = ref new Windows::UI::Xaml::Media::Imaging::BitmapImage();
    // img->BaseUri in not null because img has been added to the page.
    auto uri = ref new Windows::Foundation::Uri(img->BaseUri->AbsoluteUri, "Assets/Logo.png");
    bitmapImage->UriSource = uri;
    img->Source = bitmapImage;
    

    Using files from a network

    To use a file from a network location as an image source, use the http: or https: schemes, as shown here. Specify the absolute Uniform Resource Identifier (URI). For more info, see How to load file resources.

    <Image Source="http://www.contoso.com/images/logo.png"/>
    
    
    Image img = new Image();
    img.Source = new BitmapImage(new Uri("http://www.contoso.com/images/logo.png"));
    
    
    auto img = ref new Image();
    img->Source = ref new BitmapImage(ref new Windows::Foundation::Uri("http://www.contoso.com/images/logo.png"));
    

    Using files from local storage

    To use files that are placed in your app's local storage as an image source , use the ms-appdata: scheme, as shown here. Specify the absolute Uniform Resource Identifier (URI). For more info, see How to load file resources.

    
    <!-- Access an image file stored in the local folder -->
    <Image Source="ms-appdata:///local/images/logo.png"/>
    
    <!-- Access an image file stored in the roaming folder -->
    <Image Source="ms-appdata:///roaming/images/logo.png"/>
    
    <!-- Access an image file stored in the temp folder -->
    <Image Source="ms-appdata:///temp/images/logo.png"/>
    
    
    var uri = new System.Uri("ms-appdata:///local/images/logo.png");
    var file = await Windows.Storage.StorageFile.GetFileFromApplicationUriAsync(uri);
    
    Image img = new Image();
    img.Source = file;
    

    Using a stream source to show images from the Pictures library

    A typical use of Image elements in an app is to show pictures from the user’s Pictures library. These pictures might be accessed programmatically or through a FileOpenPicker. In either case, the StorageFile object you get can be opened as a stream, but doesn't provide a Uniform Resource Identifier (URI) reference to the image file. To use a stream as an image source, you must write code that sets your Image instance to use the stream. This can't be done in XAML alone.

    To display an individual image, use the StorageFile objects from enumerating the library and call OpenAsync(Windows.Storage.FileAccessMode,Windows.Storage.StorageOpenOptions) to obtain a stream. Use this stream to set the image source, by creating a new BitmapImage, then calling SetSourceAsync(Windows.Storage.Streams.IRandomAccessStream) and passing the stream to use as the streamSource parameter.

    This example shows how to use a FileOpenPicker to access an image file from the Pictures library and set it as the Source of an Image control. The code is already awaitable because it's waiting for the user to choose a file and it only runs after that happens. The stream to use comes from OpenAsync(Windows.Storage.FileAccessMode,Windows.Storage.StorageOpenOptions) after a StorageFile instance is returned from the async picker actions. For more info on using file pickers, see Open files and folders with a picker.

    Important

    Using a file picker in Windows Phone Store app requires additional steps that are beyond the scope of this example. For more info, see How to continue your Windows Phone app after calling a file picker.

    
    <Button Content="Get photo" Click="GetPhotoButton_Click"/>
    
    <Image x:Name="image1" Width="300"/>
    
    private async void GetPhotoButton_Click(object sender, RoutedEventArgs e)
    {
        // Set up the file picker.
        Windows.Storage.Pickers.FileOpenPicker openPicker = 
            new Windows.Storage.Pickers.FileOpenPicker();
        openPicker.SuggestedStartLocation = 
            Windows.Storage.Pickers.PickerLocationId.PicturesLibrary;
        openPicker.ViewMode = 
            Windows.Storage.Pickers.PickerViewMode.Thumbnail;
    
        // Filter to include a sample subset of file types.
        openPicker.FileTypeFilter.Clear();
        openPicker.FileTypeFilter.Add(".bmp");
        openPicker.FileTypeFilter.Add(".png");
        openPicker.FileTypeFilter.Add(".jpeg");
        openPicker.FileTypeFilter.Add(".jpg");
    
        // Open the file picker.
        Windows.Storage.StorageFile file = 
            await openPicker.PickSingleFileAsync();
    
        // 'file' is null if user cancels the file picker.
        if (file != null)
        {
            // Open a stream for the selected file.
            // The 'using' block ensures the stream is disposed
            // after the image is loaded.
            using (Windows.Storage.Streams.IRandomAccessStream fileStream =
                await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
            {
                // Set the image source to the selected bitmap.
                Windows.UI.Xaml.Media.Imaging.BitmapImage bitmapImage =
                    new Windows.UI.Xaml.Media.Imaging.BitmapImage();
    
                bitmapImage.SetSource(fileStream);
                image1.Source = bitmapImage;
            }
        }
    }
    

    This example shows how to programmatically access an image file from the Pictures library and set it as the Source of an Image control. To access the content of the Pictures library programmatically, call GetFilesAsync(Windows.Storage.Search.CommonFileQuery). Remember that you need to specify a capability to access the Pictures library programmatically.

    protected async override void OnNavigatedTo(NavigationEventArgs e)
    {
        // Get the Pictures library
        Windows.Storage.StorageFolder picturesFolder = 
            Windows.Storage.KnownFolders.PicturesLibrary;
        IReadOnlyList<StorageFolder> folders = 
            await picturesFolder.GetFoldersAsync();
    
        // Process file folders
        foreach (StorageFolder folder in folders)
        {
            // Get and process files in folder
            IReadOnlyList<StorageFile> fileList = await folder.GetFilesAsync();
            foreach (StorageFile file in fileList)
            {
                Windows.UI.Xaml.Media.Imaging.BitmapImage bitmapImage = 
                    new Windows.UI.Xaml.Media.Imaging.BitmapImage();
    
                // Open a stream for the selected file.
                // The 'using' block ensures the stream is disposed
                // after the image is loaded.
                using (Windows.Storage.Streams.IRandomAccessStream fileStream = 
                    await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
                {
                    // Set the image source to the selected bitmap.
                    Windows.UI.Xaml.Media.Imaging.BitmapImage bitmapImage =
                        new Windows.UI.Xaml.Media.Imaging.BitmapImage();
                    bitmapImage.SetSource(fileStream);
    
                    // Create an Image control.  
                    Image img = new Image();
                    img.Height = 50;
                    img.Source = bitmapImage;
    
                    // Add the Image control to the UI. 'imageGrid' is a
                    // VariableSizedWrapGrid declared in the XAML page.
                    imageGrid.Children.Add(img);
                }
            }
        }
    }
    

    Image sources and scaling

    If you are referencing images that are packaged in your app, you should create your image sources at several recommended sizes, to ensure that your app looks great when the Windows Runtime scales it. When specifying a Source for an Image as a Uniform Resource Identifier (URI), you can use a naming convention that will automatically reference the correct image resource for the current scaling as detected by the system at run-time. For specifics of the naming convention and more info, see Quickstart: Using file or image resources.

    For more info on how to design for scaling, see Responsive design 101 for or Remarks in Image.

    Image sources and resource qualifiers

    You can use automatic handling for accessing unqualified resources with current scale and culture qualifiers, or you can use ResourceManager and ResourceMap with qualifiers for culture and scale to obtain the resources directly. For more info see Resource management system or Remarks in Image. For more info on app resources and how to package image sources in an app, see Defining app resources.

  • SourceProperty
    SourceProperty
    SourceProperty
    SourceProperty

    Identifies the Source dependency property.

    public static DependencyProperty SourceProperty { get; }public static DependencyProperty SourceProperty { get; }Public Static ReadOnly Property SourceProperty As DependencyProperty

    Property Value

  • Stretch
    Stretch
    Stretch
    Stretch

    Gets or sets a value that describes how an Image should be stretched to fill the destination rectangle.

    public Stretch Stretch { get; set; }public Stretch Stretch { get; set; }Public ReadWrite Property Stretch As Stretch
    <Image Stretch="stretchValue"/>
    

    Property Value

    Remarks

    The value of the Stretch property is only relevant if the Image instance is not already using explicitly set values for the Height and/or Width property, and if the Image instance is inside a container that can stretch the image to fill some available space in layout. If you set the value of the Stretch property to None, the image always retains its natural size, even if there's a layout container that might stretch it otherwise. For more info on image sizing, see Remarks in Image.

    Image sources and scaling

    You should create your image sources at several recommended sizes, to ensure that your app looks great when Windows 8 scales it because of device scaling and resolution. This is often a better way to handling image resizing rather than applying a nondefault Stretch value. When specifying a Source for an Image, you can use a naming convention that will automatically reference the correct resource for the current scaling. For specifics of the naming convention and more info, see Quickstart: Using file or image resources.

    For more info on how to design for scaling, see UX guidelines for layout and scaling.

    Note

    A Stretch value of None doesn't work for image resources that are intended to support scaling. The scaling will be detected and the appropriate scaled resource is loaded before the layout decisions implied by the None value are applied.

  • StretchProperty
    StretchProperty
    StretchProperty
    StretchProperty

    Identifies the Stretch dependency property.

    public static DependencyProperty StretchProperty { get; }public static DependencyProperty StretchProperty { get; }Public Static ReadOnly Property StretchProperty As DependencyProperty

    Property Value

Methods

  • GetAlphaMask()
    GetAlphaMask()
    GetAlphaMask()
    GetAlphaMask()

    Returns a mask that represents the alpha channel of an image as a CompositionBrush.

    public CompositionBrush GetAlphaMask()public CompositionBrush GetAlphaMask()Public Function GetAlphaMask() As CompositionBrush

    Returns

    Remarks

    This method gets an alpha mask from an image as a CompositionBrush that you can use as an input to composition shadows and effects. The alpha mask CompositionBrush has the same alignment and stretch property values that the source XAML element applies to its rendered content so that you can use those values to correctly position shadows or effects relative to the XAML element.

    Version compatibility

    The GetAlphaMask() method is not available prior to Windows 10, version 1607. If your app’s 'minimum platform version' setting in Microsoft Visual Studio is less than the 'introduced version' shown in the Requirements block later in this page, you must design and test your app to account for this. For more info, see Version adaptive code.

    To avoid exceptions when your app runs on previous versions of Windows 10, do not call this method without first performing a runtime check. This example shows how to use the ApiInformation class to check for the presence of this method before you use it.

    if (ApiInformation.IsMethodPresent("Windows.UI.Xaml.Controls.Image", "GetAlphaMask"))
    {
        var compositionBrush = image1.GetAlphaMask();
    }
    
  • GetAsCastingSource()
    GetAsCastingSource()
    GetAsCastingSource()
    GetAsCastingSource()

    Returns the image as a CastingSource.

    public CastingSource GetAsCastingSource()public CastingSource GetAsCastingSource()Public Function GetAsCastingSource() As CastingSource

    Returns

    Remarks

    For more info about using Image as a casting source, see Media casting.

Events

  • ImageFailed
    ImageFailed
    ImageFailed
    ImageFailed

    Occurs when there is an error associated with image retrieval or format.

    public event ExceptionRoutedEventHandler ImageFailedpublic event ExceptionRoutedEventHandler ImageFailedPublic Event ImageFailed
    <Image ImageFailed="eventhandler"/>
    

    Remarks

    Conditions in which this event can occur include:

    • File not found
    • Invalid (unrecognized or unsupported) file format
    • Unknown file format decoding error after upload
    • Qualified resource reload by the system You might be able to use the ErrorMessage in event data to determine the nature of the failure.

    ImageFailed and ImageOpened are mutually exclusive. One event or the other will always file whenever an Image has a Source value set or reset.

    One scenario for handling ImageFailed is to set the UriSource of the underlying BitmapImage source to a different local image file. This can serve as a fallback value to display instead of empty space. For example, if you are trying to display an external image where it's possible that the source is no longer there, or for when the user has no Internet connection, you could set the UriSource to reference a local fallback or placeholder image that's part of your app package and is always guaranteed to be available.

    private void Image_ImageFailed(object sender, ExceptionRoutedEventArgs e) {
        Image img = sender as Image;
        BitmapImage fallbackImage = new BitmapImage(new Uri("ms-appx:///Images/fallback.png"));
        img.Width = 100; //set to known width of this source's natural size
         //might instead want image to stretch to fill, depends on scenario
        img.Source = fallbackImage;
    }
    

    Windows 8 behavior

    For Windows 8, resources can use a resource qualifier pattern to load different resources depending on device-specific scaling. However, resources aren't automatically reloaded if the scaling factor changes while the app is running. In this case apps would have to take care of reloading resources, by handling the DpiChanged event (or the deprecated LogicalDpiChanged event) and using ResourceManager API to manually reload the resource that's appropriate for the new scaling factor. Starting with Windows 8.1, any resource that was originally retrieved for your app is automatically re-evaluated if the scaling factor changes while the app is running. In addition, when that resource is the image source for an Image object, then one of the source-load events (ImageOpened or ImageFailed ) is fired as a result of the system's action of requesting the new resource and then applying it to the Image. The scenario where a run-time scale change might happen is if the user moves your app to a different monitor when more than one is available.

    If you migrate your app code from Windows 8 to Windows 8.1 you may want to account for this behavior change, because it results in ImageOpened or ImageFailed events that happen at run-time when the scale change is handled, even in cases where the Source is set in XAML. Also, if you did have code that handled DpiChanged /LogicalDpiChanged and reset the resources, you should examine whether that code is still needed given the new Windows 8.1 automatic reload behavior.

    Apps that were compiled for Windows 8 but running on Windows 8.1 continue to use the Windows 8 behavior.

  • ImageOpened
    ImageOpened
    ImageOpened
    ImageOpened

    Occurs when the image source is downloaded and decoded with no failure. You can use this event to determine the natural size of the image source.

    public event RoutedEventHandler ImageOpenedpublic event RoutedEventHandler ImageOpenedPublic Event ImageOpened
    <Image ImageOpened="eventhandler"/>
    

    Remarks

    When ImageOpened fires, that serves as the notification that any asynchronous operations have completed and all the properties of the object used as the image source are ready for use. For example, to determine the size of the image, handle ImageOpened, and check the value of the PixelWidth and PixelHeight properties on the object referenced as Source. The event data for the ImageOpened event isn't typically useful.

    Windows 8 behavior

    For Windows 8, resources can use a resource qualifier pattern to load different resources depending on device-specific scaling. However, resources aren't automatically reloaded if the scaling factor changes while the app is running. In this case apps would have to take care of reloading resources, by handling the DpiChanged event (or the deprecated LogicalDpiChanged event) and using ResourceManager API to manually reload the resource that's appropriate for the new scaling factor. Starting with Windows 8.1, any resource that was originally retrieved for your app is automatically re-evaluated if the scaling factor changes while the app is running. In addition, when that resource is the image source for an Image object, then one of the source-load events (ImageOpened or ImageFailed ) is fired as a result of the system's action of requesting the new resource and then applying it to the Image. The scenario where a run-time scale change might happen is if the user moves your app to a different monitor when more than one is available.

    If you migrate your app code from Windows 8 to Windows 8.1 you may want to account for this behavior change, because it results in ImageOpened or ImageFailed events that happen at run-time when the scale change is handled, even in cases where the Source is set in XAML. Also, if you did have code that handled DpiChanged /LogicalDpiChanged and reset the resources, you should examine whether that code is still needed given the new Windows 8.1 automatic reload behavior.

    Apps that were compiled for Windows 8 but running on Windows 8.1 continue to use the Windows 8 behavior.

Device family

Windows 10 (introduced v10.0.10240.0)

API contract

Windows.Foundation.UniversalApiContract (introduced v1)

Attributes

Windows.Foundation.Metadata.ThreadingAttribute
Windows.Foundation.Metadata.WebHostHiddenAttribute
Windows.Foundation.Metadata.StaticAttribute
Windows.Foundation.Metadata.MarshalingBehaviorAttribute
Windows.Foundation.Metadata.ContractVersionAttribute
Windows.Foundation.Metadata.ActivatableAttribute

Details

Assembly

Windows.UI.Xaml.Controls.dll