WPF异步加载BitmapImage

当你在WPF主线程中时不时需要加载图片时，界面上的Animation会因为IO操作而卡壳，要想保持动画的流畅就必须将IO操作放到后台线程中操作，如下:

01 private void ChangeImage() {
02     Image image = new Image();
03
04     new Thread(new ThreadStart(() => {
05         BitmapImage bitmap = new BitmapImage();
06         bitmap.BeginInit();
07         bitmap.UriSource = new Uri(images[index++ % images.Count]);
08         bitmap.CacheOption = BitmapCacheOption.OnLoad;
09         bitmap.EndInit();
10         bitmap.Freeze();
11
12         Dispatcher.BeginInvoke((Action)(() => {
13             image.Source = bitmap;
14             image.Stretch = Stretch.UniformToFill;
15             TransitionBox.Content = image;
16         }));
17
18     })).Start();
19 }