Image image = DataLayer.BytesToImage(blob); 系统报错说参数blob无效？？？

public static System.Drawing.Image BytesToImage(byte[] Bytes)
{
    System.IO.MemoryStream ms;
    System.IO.BinaryWriter bw;
    System.Drawing.Image imgData;
    System.Drawing.Image imgRet=null;
            
    using(ms = new MemoryStream())
    using(bw = new BinaryWriter(ms))
    {
      bw.Write(Bytes,0,Bytes.Length);
      bw.Flush();
      imgData = System.Drawing.Image.FromStream(ms);               imgRet = (System.Drawing.Image)imgData.Clone();              }
            
    return imgRet;
    
}