WPF Binding an Image using XAML and MVVM

A post describing how to bind an image such as a bitmap or png file to your viewmodel. In Visual Studio create a new WPF project: mvvm2 Observe that this creates the initial default XAML for the main window as shown: MainWindow.xaml [code language="xml"] <Window x:Class="MVVM.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="350" Width="525"> <Grid> </Grid> </Window> [/code] Which when running the program produces the following blank window: Initial Window mvvm1 Now we need to add the ViewModel class, as is used in the Model-View ViewModel pattern. In Visual Studio add a new class representing the ViewModel for our main window XAML and call it MainWindowViewModel.cs: mvvm3 And configure the code so we have a property for returning the bitmap image in a format that is suitable for our WPF. Also in this class is a static method for converting a general bitmap format into a BitmapSource type: [code language="csharp"] using System; using System.Drawing.Imaging; using System.Drawing; using System.Windows.Media.Imaging; using System.Windows; namespace MVVM { public static class BitmapConversion { public static BitmapSource BitmapToBitmapSource(Bitmap source) { return System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap( source.GetHbitmap(), IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions()); } } public class MainWindowViewModel { private BitmapSource _bitmapSource; public MainWindowViewModel() { Bitmap bitmap = (Bitmap) Bitmap.FromFile(@"c:\dump\bulb.png", true); _bitmapSource = BitmapConversion.BitmapToBitmapSource(bitmap); } public BitmapSource ButtonSource { get { return _bitmapSource; } } } } [/code] If you have trouble compiling the source make sure all the references are installed, particularly System.Drawing: mvvm4 And of course be sure that your program is able to find the location of the image file that we are binding to, in my example it is "C:\dump\bulb.png": [code language="csharp"] public MainWindowViewModel() { Bitmap bitmap = (Bitmap) Bitmap.FromFile(@"c:\dump\bulb.png", true); _bitmapSource = BitmapConversion.BitmapToBitmapSource(bitmap); } [/code] Modify the MainWindow.xaml to include the DataContext and to insert a new button containing the image we wish to bind to: [code language="xml"] <Window x:Class="MVVM.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:VM="clr-namespace:MVVM" Title="MainWindow" Height="234" Width="326"> <Window.DataContext> <VM:MainWindowViewModel /> </Window.DataContext> <Grid> <Button HorizontalAlignment="Left" Margin="35,0,0,138" VerticalAlignment="Bottom" Width="75" Height="29"> <Image Source="{Binding ButtonSource}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="0"> </Image> </Button> </Grid> </Window> [/code] Compiling and running this gives the following Window, this time with button containing the XAML-bounded image: mvvm5 Download Visual Studio 2010 project from here: https://www.technical-recipes.com/Downloads/MVVM.zip

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