Binding to BitmapImage retrieved from Active Directory not working

Question

I have a piece of code that retrieves a user's image from Active Directory and then updates a bound BitmapImage property with it.

The XAML looks like:

            <Image Width="30"
                   Height="30"
                   Margin="10"
                   DockPanel.Dock="Left"
                   Source="{Binding UserImage}"
                   VerticalAlignment="Top" />

The property is defined as:

        public BitmapImage UserImage
        {
            get
            {
                return _userImage;
            }
            set
            {
                if (_userImage != value)
                {
                    _userImage = value;
                    PropertyChanged(this, new PropertyChangedEventArgs("UserImage"));
                }
            }
        }

Finally, the code that updates the property is:

            PrincipalContext principleContext = new PrincipalContext(ContextType.Domain, HAL_Globals.domain);
            UserPrincipal user = UserPrincipal.FindByIdentity(principleContext,    IdentityType.SamAccountName, HAL_Globals.domain + "\\" + _usernameSearchText);
            DirectoryEntry userEntry = (user.GetUnderlyingObject() as DirectoryEntry);

            if (userEntry != null)
            {
                using (MemoryStream stream = new MemoryStream(userEntry.Properties["thumbnailPhoto"].Value as byte[]))
                {
                    BitmapImage userImage = new BitmapImage();
                    userImage.BeginInit();
                    userImage.StreamSource = stream;
                    userImage.EndInit();

                    UserImage = userImage;
                }
            }

The problem is the image in the view is not being updated with anything. I have debugged the image being created and it looks ok, however the debugging tool doesn't support previewing that type so it's hard to verify. I have tried binding to an 64 bit encoded image string instead but had no luck. Any help or guidance would be appreciated.

Answer 1

You have to set BitmapCacheOptions.OnLoad when you want to close the stream directly after initializing the BitmapImage:

var userImage = new BitmapImage();

using (var stream = new MemoryStream(...))
{
    userImage.BeginInit();
    userImage.CacheOption = BitmapCacheOption.OnLoad;
    userImage.StreamSource = stream;
    userImage.EndInit();
}

UserImage = userImage;

See the Remarks section in BitmapImage.CacheOption:

Set the CacheOption to BitmapCacheOption.OnLoad if you wish to close a stream used to create the BitmapImage. ...