MemoryStream ms = new MemoryStream();
yourBitmap.Save(ms, ImageFormat.Bmp);
byte[] bitmapData = ms.ToArray();

试试下面的方法:

MemoryStream stream = new MemoryStream();
Bitmap bitmap = new Bitmap();
bitmap.Save(stream, ImageFormat.Jpeg);

byte[] byteArray = stream.GetBuffer();

确保你使用:

System.Drawing & using System.Drawing.Imaging;

使用内存流而不是文件流，就像这样:

MemoryStream ms = new MemoryStream();
bmp.Save (ms, ImageFormat.Jpeg);
byte[] bmpBytes = ms.ToArray();

更简单:

return (byte[])System.ComponentModel.TypeDescriptor.GetConverter(pImagen).ConvertTo(pImagen, typeof(byte[]))

将图像保存到MemoryStream，然后获取字节数组。

http://msdn.microsoft.com/en-us/library/ms142148.aspx

  Byte[] data;

  using (var memoryStream = new MemoryStream())
  {
    image.Save(memoryStream, ImageFormat.Bmp);

    data = memoryStream.ToArray();
  }

我相信你可以简单地做到:

ImageConverter converter = new ImageConverter();
var bytes = (byte[])converter.ConvertTo(img, typeof(byte[]));