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copied!<p>Yes, it is possible to use images from isolated storage in the app UI. It requires loading the image from the file into the <code>BitmapImage</code> and then binding <code>ImageSource</code> of your control to that <code>BitmapImage</code>. I'm using the following approach:</p> <p>First, there's a method to load image asynchronously:</p> <pre><code>private Task<Stream> LoadImageAsync(string filename) { return Task.Factory.StartNew<Stream>(() => { if (filename == null) { throw new ArgumentException("one of parameters is null"); } Stream stream = null; using (var isoStore = IsolatedStorageFile.GetUserStoreForApplication()) { if (isoStore.FileExists(filename)) { stream = isoStore.OpenFile(filename, System.IO.FileMode.Open, FileAccess.Read); } } return stream; }); } </code></pre> <p>Then it can be used like this:</p> <pre><code>public async Task<BitmapSource> FetchImage() { BitmapImage image = null; using (var imageStream = await LoadImageAsync(doc.ImagePath)) { if (imageStream != null) { image = new BitmapImage(); image.SetSource(imageStream); } } return image; } </code></pre> <p>And finally you just assign return value of <code>FetchImage()</code> method to some of your view model's property, to which the UI element is bound. Of course, your view model should properly implement <code>INotifyPropertyChanged</code> interface for this approach to work reliably.</p> <hr> <p>If you want to use attached properties approach, here's how you do it:</p> <pre><code>public class IsoStoreImageSource : DependencyObject { public static void SetIsoStoreFileName(UIElement element, string value) { element.SetValue(IsoStoreFileNameProperty, value); } public static string GetIsoStoreFileName(UIElement element) { return (string)element.GetValue(IsoStoreFileNameProperty); } // Using a DependencyProperty as the backing store for IsoStoreFileName. This enables animation, styling, binding, etc... public static readonly DependencyProperty IsoStoreFileNameProperty = DependencyProperty.RegisterAttached("IsoStoreFileName", typeof(string), typeof(IsoStoreImageSource), new PropertyMetadata("", Changed)); private static void Changed(DependencyObject d, DependencyPropertyChangedEventArgs e) { Image img = d as Image; if (img != null) { var path = e.NewValue as string; SynchronizationContext uiThread = SynchronizationContext.Current; Task.Factory.StartNew(() => { using (var isoStore = IsolatedStorageFile.GetUserStoreForApplication()) { if (isoStore.FileExists(path)) { var stream = isoStore.OpenFile(path, System.IO.FileMode.Open, FileAccess.Read); uiThread.Post(_ => { var _img = new BitmapImage(); _img.SetSource(stream); img.Source = _img; }, null); } } }); } } } </code></pre> <p>And then in XAML:</p> <pre><code><Image local:IsoStoreImageSource.IsoStoreFileName="{Binding Path}" /> </code></pre> <p>Some limitations of this approach:</p> <ul> <li>It only works on <code>Image</code> control, though you can change this to a whichever type you want. It's just not very generic.</li> <li>Performance-wise, it will use a thread from the threadpool every time image source is changed. It's the only way to do asynchronous read from isolated storage on Windows Phone 8 right now. And you definitely don't want to do this synchronously.</li> </ul> <p>But it has one one important advantage:</p> <ul> <li>It works! :)</li> </ul>

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