FrameworkElement.BaseUri Property

Definition

Namespace:

Microsoft.UI.Xaml

Gets a Uniform Resource Identifier (URI) that represents the base URI for an XAML-constructed object at XAML load time. This property is useful for URI resolution at run time.

public:
 property Uri ^ BaseUri { Uri ^ get(); };

Uri BaseUri();

public System.Uri BaseUri { get; }

var uri = frameworkElement.baseUri;

Public ReadOnly Property BaseUri As Uri

Property Value

Uri Uri

The base Uniform Resource Identifier (URI) for an object at XAML load time.

Examples

This example uses BaseUri in an event handler that resets an image source to a backup/default. BaseUri is used for the "path" part of a new Uniform Resource Identifier (URI) that is used for a BitmapImage constructor call, the rest of the URI points to an image file that the app has in its resources. To see this code in the context of a UWP app, see the CameraCaptureUI sample.

void SDKSample::Page::Reset_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
    rootPage->NotifyUser("The photo will be shown here.", NotifyType::StatusMessage); 
    ResetButton->Visibility = Windows::UI::Xaml::Visibility::Collapsed; 
    CapturedPhoto->Source = ref new BitmapImage(ref new Windows::Foundation::Uri(BaseUri->AbsoluteUri, "Assets/placeholder-sdk.png")); 
     // Remove file from Application Data 
    appSettings->Remove("capturedPhoto"); 
}

private void Reset_Click(object sender, RoutedEventArgs e)
{
    ResetButton.Visibility = Visibility.Collapsed;
    CapturedPhoto.Source = new BitmapImage(new Uri(this.BaseUri, "Assets/placeholder-sdk.png"));

    // Clear file path in Application Data 
    appSettings.Remove(photoKey);
}

Remarks

The XAML parser can evaluate references to resources based on the context of the object in a page, and can thus evaluate what appear to be partial paths in a Uniform Resource Identifier (URI) property. For run-time code, the definition rules for the Uniform Resource Identifier (URI) types don't permit partial paths. At run time, you can use BaseUri from the scope of an object that was created by parsing a XAML page in order to get the "path" part of a URI, and then complete the URI with a particular resource reference.