MemoryStream ms = new MemoryStream(bytes);
ms.Position = 0;
Image img = Image.FromStream(ms);
ms.Close();

System.Text.UnicodeEncoding converter = new System.Text.UnicodeEncoding();
byte[] inputBytes =converter.GetBytes(inputString);
string inputString = converter.GetString(inputBytes);string inputString = System.Convert.ToBase64String(inputBytes);
byte[] inputBytes = System.Convert.FromBase64String(inputString);
FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);

/// 将 Stream 转成 byte[]
public byte[] StreamToBytes(Stream stream)
{byte[] bytes = new byte[stream.Length];stream.Read(bytes, 0, bytes.Length);// 设置当前流的位置为流的开始stream.Seek(0, SeekOrigin.Begin);return bytes;
}/// 将 byte[] 转成 Stream
public Stream BytesToStream(byte[] bytes)
{Stream stream = new MemoryStream(bytes);return stream;
}

// 将Stream读取到文件
public void StreamToFile(Stream stream,string fileName)
{// 把 Stream 转换成 byte[]byte[] bytes = new byte[stream.Length];stream.Read(bytes, 0, bytes.Length);// 设置当前流的位置为流的开始stream.Seek(0, SeekOrigin.Begin);// 把 byte[] 写入文件FileStream fs = new FileStream(fileName, FileMode.Create);BinaryWriter bw = new BinaryWriter(fs);bw.Write(bytes);bw.Close();fs.Close();
}// 从文件读取Stream
public Stream FileToStream(string fileName)
{            // 打开文件FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);// 读取文件的 byte[]byte[] bytes = new byte[fileStream.Length];fileStream.Read(bytes, 0, bytes.Length);fileStream.Close();// 把 byte[] 转换成 StreamStream stream = new MemoryStream(bytes);return stream;
}

//Bitmap 转化为 Byte[]
Bitmap BitReturn = new Bitmap();
byte[] bReturn = null;
MemoryStream ms = new MemoryStream();
BitReturn.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
bReturn = ms.GetBuffer();