Convert Bitmap Image to byte array (Windows phone

问题:

I am new to windows phone dev. My small app need a bytesarray from image (photo gallery). I tried many ways to convert, but it did not work fine.

here is my code:

public static byte[] ConvertBitmapImageToByteArray(BitmapImage bitmapImage)
    {
        using (var ms = new MemoryStream())
        {
            var btmMap = new WriteableBitmap(bitmapImage.PixelWidth, bitmapImage.PixelHeight);
            // write an image into the stream
            btmMap.SaveJpeg(ms, bitmapImage.PixelWidth, bitmapImage.PixelHeight, 0, 100);
            return ms.ToArray();
        }
    }

But then I saved this byte array to image in photogallery, I was be a black image!

public static void SavePicture2Library(byte[] bytes)
    {
        var library = new MediaLibrary();
        var name = "image_special";
        library.SavePicture(name, bytes);
    }

Could anyone help me? Please test your code :( Thanks so much!

---

Update resolved!

var wBitmap = new WriteableBitmap(bitmapImage);
            wBitmap.SaveJpeg(stream, wBitmap.PixelWidth, wBitmap.PixelHeight, 0, 100);
            stream.Seek(0, SeekOrigin.Begin);
            data = stream.GetBuffer();

回答1:

To anyone who finds this, this works;

Image to bytes;

public static byte[] ImageToBytes(BitmapImage img)
        {
            using (MemoryStream ms = new MemoryStream())
            {
                WriteableBitmap btmMap = new WriteableBitmap(img);
                System.Windows.Media.Imaging.Extensions.SaveJpeg(btmMap, ms, img.PixelWidth, img.PixelHeight, 0, 100);
                img = null;
                return ms.ToArray();
            }
        }

Bytes to Image

public static BitmapImage BytesToImage(byte[] bytes)
        {
            BitmapImage bitmapImage = new BitmapImage();
            try
            {
                using (MemoryStream ms = new MemoryStream(bytes))
                {
                    bitmapImage.SetSource(ms);
                    return bitmapImage;
                }
            }
            finally { bitmapImage = null; }
        }

回答2:

for windows phone 8

using System.IO;

public static class FileToByteArray
{
    public static byte[] Convert(string pngBmpFileName)
    {
        System.IO.FileStream fileStream = File.OpenRead(pngBmpFileName);

        using (MemoryStream memoryStream = new MemoryStream())
        {
            fileStream.CopyTo(memoryStream);
            return memoryStream.ToArray();
        }
    }
}
byte[] PasPhoto = FileToByteArray.Convert("Images/NicePhoto.png")