ImageBrush中的图片如何加载到到MemoryStream

            ImageBrush ib  =  new  ImageBrush();
            Bitmap bitmap;
            ib.ImageSource  =  image1.Source;
            BitmapEncoder encoder  =  new  PngBitmapEncoder();
             // PngBitmapEncoder encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(ib.ImageSource  as  BitmapSource));
            encoder.Save(ms);

            ms.Flush();

 

相反的情况，从 MemoryStream加载图片到ImageBrush

                ImageBrush imageBrush = new ImageBrush();
                ImageSourceConverter imageSourceConverter = new ImageSourceConverter();
                imageBrush.ImageSource = (ImageSource)imageSourceConverter.ConvertFrom(stream);

                image1.Source = imageBrush.ImageSource;

 

以上stream是一个MemoryStream