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WebView.CapturePreviewToStreamAsync(IRandomAccessStream) Method

Definition

Creates an image of the current WebView contents and writes it to the specified stream.

public:
 virtual IAsyncAction ^ CapturePreviewToStreamAsync(IRandomAccessStream ^ stream) = CapturePreviewToStreamAsync;
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncAction CapturePreviewToStreamAsync(IRandomAccessStream const& stream);
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncAction CapturePreviewToStreamAsync(IRandomAccessStream stream);
function capturePreviewToStreamAsync(stream)
Public Function CapturePreviewToStreamAsync (stream As IRandomAccessStream) As IAsyncAction

Parameters

stream
IRandomAccessStream

The stream to write the image to.

Returns

An asynchronous action to await the capture operation.

Attributes

Examples

This example shows how to use this method to create a thumbnail image of the current content. For the complete example, see the WebView control sample.

private async void bookmarkBtn_Click(object sender, RoutedEventArgs e)
{
    InMemoryRandomAccessStream ms = new InMemoryRandomAccessStream();
    await webView8.CapturePreviewToStreamAsync(ms);

    // Create a small thumbnail.
    int longlength = 180, width = 0, height = 0;
    double srcwidth = webView8.ActualWidth, srcheight = webView8.ActualHeight;
    double factor = srcwidth / srcheight;
    if (factor < 1)
    {
        height = longlength;
        width = (int)(longlength * factor);
    }
    else
    {
        width = longlength;
        height = (int)(longlength / factor);
    }
    BitmapSource small = await resize(width, height, ms);

    BookmarkItem item = new BookmarkItem();
    item.Title = webView8.DocumentTitle;
    item.PageUrl = webView8.Source;
    item.Preview = small;

    bookmarks.Add(item);
}

Applies to

See also