Metro APP - BitmapImage to Byte []或从Web下载图像并将其转换为Byte []数组(Metro APP - BitmapImage to Byte[] or Download Image from Web and convert it to a Byte[] Array)

 有没有办法将BitmapImage（Windows.UI.Xaml.Media.BitmapImage）转换为Byte []数组？ 我没有尝试过任何工作....另一种可能的情况（如果BitmapImage无法转换为Byte数组）是从web下载图像然后将其转换为数组... 
 
 但我不知道我怎么能这样做......如果有人有想法，那将是非常好的。 
 
 目前尝试： 
 
        HttpClient http = new HttpClient();
        Stream resp = await http.GetStreamAsync("http://localhost/img/test.jpg");

        var ras = new InMemoryRandomAccessStream();
        await resp.CopyToAsync(ras.AsStreamForWrite());

        BitmapImage bi = new BitmapImage();
        bi.SetSource(ras);


        byte[] pixeBuffer = null;

        using (MemoryStream ms = new MemoryStream())
        {
            int i = bi.PixelHeight;
            int i2 = bi.PixelWidth;
            WriteableBitmap wb = new WriteableBitmap(bi.PixelWidth, bi.PixelHeight);

            Stream s1 = wb.PixelBuffer.AsStream();
            s1.CopyTo(ms);

            pixeBuffer = ms.ToArray();
        }
 
 但它不起作用... i＆i2总是设置为0.所以ras无法正常工作......发生了什么事？ 
 
 谢谢 

Is there a way to convert a BitmapImage (Windows.UI.Xaml.Media.BitmapImage) to an Byte[] Array? Nothing I've tried work.... Another possible scenario (if BitmapImage cannot be converted to Byte array) is to download the image from web and then convert it to an array...
 
But I don't know how I can do that... It would be really nice, if someone have an idea.
 
Current try:
 
        HttpClient http = new HttpClient();
        Stream resp = await http.GetStreamAsync("http://localhost/img/test.jpg");

        var ras = new InMemoryRandomAccessStream();
        await resp.CopyToAsync(ras.AsStreamForWrite());

        BitmapImage bi = new BitmapImage();
        bi.SetSource(ras);


        byte[] pixeBuffer = null;

        using (MemoryStream ms = new MemoryStream())
        {
            int i = bi.PixelHeight;
            int i2 = bi.PixelWidth;
            WriteableBitmap wb = new WriteableBitmap(bi.PixelWidth, bi.PixelHeight);

            Stream s1 = wb.PixelBuffer.AsStream();
            s1.CopyTo(ms);

            pixeBuffer = ms.ToArray();
        }
 
But it doesn't work... i & i2 are always set to 0. So ras doesn't work correctly.... What's going on?
 
Thanks

原文：https://stackoverflow.com/questions/10472282