c#中字节数组byte[]、图片image、流stream，字符串string、内存流MemoryStream、文件file，之间的转换

字节数组byte[]与图片image之间的转化

字节数组转换成图片

public static Image byte2img(byte[] buffer)
{
  MemoryStream ms = new MemoryStream(buffer);
  ms.Position = 0;
  Image img = Image.FromStream(ms);
  ms.Close();
  return img;
}

图片转化为字节数组

public static byte[] byte2img(Bitmap Bit)
{
    byte[] back = null;
    MemoryStream ms = new MemoryStream();
    Bit.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
    back = ms.GetBuffer();
    return back;
}

字节数组byte[]与字符串string之间的编码解码

字符串到字节数组的编码

public static byte[] str2byte(string str)
{
    byte[] data = System.Text.Encoding.UTF8.GetBytes(param);
    //byte[] data = Convert.FromBase64String(param);
    //有很多种编码方式
    return data;
}

字节数组到字符串的解码

public static string str2byte(byte[] data)
{
    string str = System.Text.Encoding.UTF8.GetString(data);
    //str = Convert.ToBase64String(data);
    //有很多种编码方式
    return str;
}

字节数组byte[]与内存流MemoryStream之间的转换

字节数组转化为输入内存流

public static MemoryStream byte2stream(byte[] data)
{
    MemoryStream inputStream = new MemoryStream(data);
    return inputStream;
}

输出内存流转化为字节数组

public static byte[] byte2stream(MemoryStream outStream)
{
    return outStream.ToArray();
}

字节数组byte[]与流stream之间的转换

将 Stream 转成 byte[]

public byte[] stream2byte(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 byte2stream(byte[] bytes)
{
    Stream stream = new MemoryStream(bytes);
    return stream;
}

流Stream 和 文件file之间的转换

将 Stream 写入文件

public void stream2file(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 file2stream(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 Stream
    Stream stream = new MemoryStream(bytes);
    return stream;
}