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How to: Paint an Area with an Image

This example shows how to use the ImageBrush class to paint an area with an image. An ImageBrush displays a single image, which is specified by its ImageSource property.

Example

The following example paints the Background of a button by using an ImageBrush.


using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media.Imaging;
using System.Windows.Media;

namespace Microsoft.Samples.Graphics.UsingImageBrush
{

    public class PaintingWithImagesExample : Page
    {

        public PaintingWithImagesExample()
        {
            Background = Brushes.White;
            StackPanel mainPanel = new StackPanel();
            mainPanel.Margin = new Thickness(20.0);

            // Create a button.
            Button berriesButton = new Button();
            berriesButton.Foreground = Brushes.White;
            berriesButton.FontWeight = FontWeights.Bold;
            FontSizeConverter sizeConverter = new FontSizeConverter();
            berriesButton.FontSize = (Double)sizeConverter.ConvertFromString("16pt");
            berriesButton.FontFamily = new FontFamily("Verdana");
            berriesButton.Content = "Berries";
            berriesButton.Padding = new Thickness(20.0);
            berriesButton.HorizontalAlignment = HorizontalAlignment.Left;

            // Create an ImageBrush.
            ImageBrush berriesBrush = new ImageBrush();
            berriesBrush.ImageSource =
                new BitmapImage(
                    new Uri(@"sampleImages\berries.jpg", UriKind.Relative)
                );

            // Use the brush to paint the button's background.
            berriesButton.Background = berriesBrush;

            mainPanel.Children.Add(berriesButton);
            this.Content = mainPanel;
        }
    }
}

By default, an ImageBrush stretches its image to completely fill the area that you are painting. In the preceding example, the image is stretched to fill the button, possibly distorting the image. You can control this behavior by setting the Stretch property of TileBrush to Uniform or UniformToFill, which causes the brush to preserve the aspect ratio of the image.

If you set the Viewport and TileMode properties of an ImageBrush, you can create a repeating pattern. The following example paints a button by using a pattern that is created from an image.


using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media.Imaging;
using System.Windows.Media;

namespace Microsoft.Samples.Graphics.UsingImageBrush
{

    public class TiledImageBrushExample : Page
    {

        public TiledImageBrushExample()
        {
            Background = Brushes.White;
            StackPanel mainPanel = new StackPanel();
            mainPanel.Margin = new Thickness(20.0);

            // Create a button.
            Button berriesButton = new Button();
            berriesButton.Foreground = Brushes.White;
            berriesButton.FontWeight = FontWeights.Bold;
            FontSizeConverter sizeConverter = new FontSizeConverter();
            berriesButton.FontSize = (Double)sizeConverter.ConvertFromString("16pt");
            berriesButton.FontFamily = new FontFamily("Verdana");
            berriesButton.Content = "Berries";
            berriesButton.Padding = new Thickness(20.0);
            berriesButton.HorizontalAlignment = HorizontalAlignment.Left;

            // Create an ImageBrush.
            ImageBrush berriesBrush = new ImageBrush();
            berriesBrush.ImageSource =
                new BitmapImage(
                    new Uri(@"sampleImages\berries.jpg", UriKind.Relative)
                );

            // Set the ImageBrush's Viewport and TileMode
            // so that it produces a pattern from
            // the image.
            berriesBrush.Viewport = new Rect(0,0,0.5,0.5);
            berriesBrush.TileMode = TileMode.FlipXY;

            // Use the brush to paint the button's background.
            berriesButton.Background = berriesBrush;

            mainPanel.Children.Add(berriesButton);
            this.Content = mainPanel;
        }
    }
}

Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media.Imaging
Imports System.Windows.Media

Namespace Microsoft.Samples.Graphics.UsingImageBrush

    Public Class TiledImageBrushExample
        Inherits Page

        Public Sub New()
            Background = Brushes.White
            Dim mainPanel As New StackPanel()
            mainPanel.Margin = New Thickness(20.0)

            ' Create a button.
            Dim berriesButton As New Button()
            With berriesButton
                .Foreground = Brushes.White
                .FontWeight = FontWeights.Bold
                Dim sizeConverter As New FontSizeConverter()
                .FontSize = CType(sizeConverter.ConvertFromString("16pt"), Double)
                .FontFamily = New FontFamily("Verdana")
                .Content = "Berries"
                .Padding = New Thickness(20.0)
                .HorizontalAlignment = HorizontalAlignment.Left
            End With

            ' Create an ImageBrush.
            Dim berriesBrush As New ImageBrush()
            berriesBrush.ImageSource = New BitmapImage(New Uri("sampleImages\berries.jpg", UriKind.Relative))

            ' Set the ImageBrush's Viewport and TileMode
            ' so that it produces a pattern from
            ' the image.
            berriesBrush.Viewport = New Rect(0, 0, 0.5, 0.5)
            berriesBrush.TileMode = TileMode.FlipXY

            ' Use the brush to paint the button's background.
            berriesButton.Background = berriesBrush

            mainPanel.Children.Add(berriesButton)
            Me.Content = mainPanel
        End Sub
    End Class
End Namespace

For more information about the ImageBrush class, see Painting with Images, Drawings, and Visuals.

This code example is part of a larger example that is provided for the ImageBrush class. For the complete sample, see ImageBrush Sample.

See also