How to capture a Node with transparent

Question

For example, I have a UWP app, which has a node "Button" on it. Now, I want to make a snap for this Button. And, the output only includes this Button.

For JavaFX, we have the function "node.snapshot()", how about C# with UWP?

Answer 1

You could use RenderTargetBitmap class(which represents an image source that can be populated with the combined contents of a XAML visual tree) to do the job.

For example:

//Page.xaml 
<StackPanel>
    <Button x:Name="capturedButton" Content="capture me" Margin="10"/>
    <Button x:Name="button" Content="click me" Margin="10" Click="button_Click"/>
    <Image x:Name="image" Margin="10" Width="200" Height="200" Stretch="None"/>
</StackPanel>

//Page.xaml.cs
private async void button_Click(object sender, RoutedEventArgs e)
{
    RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap();
    await renderTargetBitmap.RenderAsync(capturedButton);
    image.Source = renderTargetBitmap;
}