BitmapImage to byte[]

问题:

I have a BitmapImage that I'm using in a WPF application, I later want to save it to a database as a byte array (I guess it's the best way), how can I perform this conversion?

Or, alternatively, is there a better way to save a BitmapImage (or any of its base classes, BitmapSource or ImageSource) to a data repository?

回答1:

To convert to a byte[] you can use a MemoryStream:

byte[] data;
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmapImage));
using(MemoryStream ms = new MemoryStream())
{
    encoder.Save(ms);
    data = ms.ToArray();
}

Instead of the JpegBitmapEncoder you can use whatever BitmapEncoder you like as casperOne said.

If you are using MS SQL you could also use a image-Column as MS SQL supports that datatype, but you still would need to convert the BitmapImage somehow.

回答2:

You will have to use an instance of a class that derives from BitmapEncoder (such as BmpBitmapEncoder) and call the Save method to save the BitmapSource to a Stream.

You would choose the specific encoder depending on the format you want to save the image in.

回答3:

write it to a MemoryStream, then you can access the bytes from there. something kinda like this:

public Byte[] ImageToByte(BitmapImage imageSource)
{
    Stream stream = imageSource.StreamSource;
    Byte[] buffer = null;
    if (stream != null && stream.Length > 0)
    {
        using (BinaryReader br = new BinaryReader(stream))
        {
            buffer = br.ReadBytes((Int32)stream.Length);
        }
    }

    return buffer;
}

回答4:

Just use a MemoryStream.

byte[] data = null;

using(MemoryStream ms = new MemoryStream())
{
    bitmapImage.Save(ms);
    data = ms.ToArray();
}