在涉及IO操作时，Stream 和 Byte[] 是最常用的，以下就做一个简单纪录

Byte[]
=====

1. BitConverter

将基础数据类型与字节数组相互转换。注意string不是基础类型，而且该方法在不同平台间传递可能有误。

int i = 13;
byte[] bs = BitConverter.GetBytes(i);
Console.WriteLine(BitConverter.ToInt32(bs, 0));

2. Encoding

注意慎用Encoding.Default，其值取自操作系统当前的设置，因此在不同语言版本的操作系统是不相同的。建议使用UTF8或者GetEncoding("gb2312")。

string s = "abc";
byte[] bs = Encoding.UTF8.GetBytes(s);
Console.WriteLine(Encoding.UTF8.GetString(bs));

3. BinaryFormatter

以二进制格式将对象或整个连接对象图形序列化和反序列化。

using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;

[Serializable]
class Data
{
  private int x = 13;

  public void Test()
  {
    Console.WriteLine(x);
  }
}

static void Main(string[] args)
{
  Data data = new Data();

  MemoryStream stream = new MemoryStream();
  BinaryFormatter formatter = new BinaryFormatter();
  formatter.Serialize(stream, data);

  byte[] bs = stream.ToArray();

  MemoryStream stream2 = new MemoryStream(bs);
  Data data2 = (Data)formatter.Deserialize(stream2);
  data2.Test();
}

Stream
=====

Stream 包含 FileStream、MemoryStream、BufferedStream、NetworkStream、CryptoStream。
常用的方法和属性包括：Close / Flush / Seek / Read / Write / CanSeek等，可参考SDK。
Stream 并不能直接操作基元和对象类型，需要将其转换成Byte[]才能进行读写操作。以下记录几种转换方式。

byte[] bs = Encoding.UTF8.GetBytes("abc");

// 1. Byte[] to Stream
MemoryStream stream = new MemoryStream(bs);
      
// 2. Byte[] to Stream
MemoryStream stream2 = new MemoryStream();
stream2.Write(bs, 0, bs.Length);

// 3. Byte[] to Stream
FileStream stream3 = new FileStream("a.dat", FileMode.Create, FileAccess.ReadWrite);
stream3.Write(bs, 0, bs.Length);
stream3.Close();

// 4. Stream to Byte[]
byte[] bs2 = stream.ToArray();

// 5. Stream to Byte[] (Buffer Length = 256)
byte[] bs3 = stream2.GetBuffer();
      
// 6. Stream to Byte[]
FileStream stream4 = new FileStream("a.dat", FileMode.Open, FileAccess.Read);
stream4.Seek(0, SeekOrigin.Begin);
byte[] bs4 = new byte[3];
stream4.Read(bs4, 0, bs4.Length);

后记

 

/* - - - - - - - - - - - - - - - - - - - - - - - -
* Stream 和 byte[] 之间的转换
* - - - - - - - - - - - - - - - - - - - - - - - */
/// <summary>
/// 将 Stream 转成 byte[]
/// </summary>
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;
}

/// <summary>
/// 将 byte[] 转成 Stream
/// </summary>
public Stream BytesToStream(byte[] bytes)
{
Stream stream = new MemoryStream(bytes);
return stream;
}

/* - - - - - - - - - - - - - - - - - - - - - - - -
* Stream 和 文件之间的转换
* - - - - - - - - - - - - - - - - - - - - - - - */
/// <summary>
/// 将 Stream 写入文件
/// </summary>
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();
}

/// <summary>
/// 从文件读取 Stream
/// </summary>
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 Stream
Stream stream = new MemoryStream(bytes);
return stream;
}

 

转载于:https://www.cnblogs.com/wzhxj/archive/2011/09/23/2185892.html